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Bazer FW, Burghardt RC, Johnson GA, Spencer TE, Wu G. Mechanisms for the establishment and maintenance of pregnancy: synergies from scientific collaborations. Biol Reprod 2018; 99:225-241. [PMID: 29462279 PMCID: PMC6044348 DOI: 10.1093/biolre/ioy047] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 02/13/2018] [Accepted: 02/15/2018] [Indexed: 11/14/2022] Open
Abstract
Research on the functions of interferon tau (IFNT) led to the theory of pregnancy recognition signaling in ruminant species. But IFNT does much more as it induces expression of interferon regulatory factor 2 (IRF2) in uterine luminal (LE), superficial glandular (sGE), but not glandular (GE) epithelia. First, IRF2 silences transcription of the estrogen receptor alpha gene and, indirectly, transcription of the oxytocin receptor gene to abrogate development of the luteolytic mechanism to prevent regression of the corpus luteum and its production of progesterone for establishing and maintaining pregnancy. Second, IRF2 silences expression of classical interferon-stimulated genes in uterine LE and sGE; however, uterine LE and sGE respond to progesterone (P4) and IFNT to increase expression of genes for transport of nutrients into the uterine lumen such as amino acids and glucose. Other genes expressed by uterine LE and sGE encode for adhesion molecules such as galectin 15, cathepsins, and cystatins for tissue remodeling, and hypoxia-inducible factor relevant to angiogenesis and survival of blastocysts in a hypoxic environment. IFNT is also key to a servomechanism that allows uterine epithelia, particularly GE, to proliferate and to express genes in response to placental lactogen and placental growth hormone in sheep. The roles of secreted phosphoprotein 1 are also discussed regarding its role in implantation in sheep and pigs, as well as its stimulation of expression of mechanistic target of rapamycin mRNA and protein which is central to proliferation, migration, and gene expression in the trophectoderm cells.
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Affiliation(s)
- Fuller W Bazer
- Department of Animal Science, Texas A&M University, College Station, Texas, USA
| | - Robert C Burghardt
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Gregory A Johnson
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Thomas E Spencer
- Division of Animal Science, University of Missouri, Columbia, Missouri, USA
| | - Guoyao Wu
- Department of Animal Science, Texas A&M University, College Station, Texas, USA
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Fan SJ, Goberdhan DCI. PATs and SNATs: Amino Acid Sensors in Disguise. Front Pharmacol 2018; 9:640. [PMID: 29971004 PMCID: PMC6018406 DOI: 10.3389/fphar.2018.00640] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 05/29/2018] [Indexed: 11/30/2022] Open
Abstract
Solute Carriers (SLCs) are involved in the transport of substances across lipid bilayers, including nutrients like amino acids. Amino acids increase the activity of the microenvironmental sensor mechanistic Target of Rapamycin Complex 1 (mTORC1) to promote cellular growth and anabolic processes. They can be brought in to cells by a wide range of SLCs including the closely related Proton-assisted Amino acid Transporter (PAT or SLC36) and Sodium-coupled Neutral Amino acid Transporter (SNAT or SLC38) families. More than a decade ago, the first evidence emerged that members of the PAT family can act as amino acid-stimulated receptors, or so-called "transceptors," connecting amino acids to mTORC1 activation. Since then, further studies in human cell models have suggested that other PAT and SNAT family members, which share significant homology within their transmembrane domains, can act as transceptors. A paradigm shift has also led to the PATs and SNATs at the surface of multiple intracellular compartments being linked to the recruitment and activation of different pools of mTORC1. Much focus has been on late endosomes and lysosomes as mTORC1 regulatory hubs, but more recently a Golgi-localized PAT was shown to be required for mTORC1 activation. PATs and SNATs can also traffic between the cell surface and intracellular compartments, with regulation of this movement providing a means of controlling their mTORC1 regulatory activity. These emerging features of PAT and SNAT amino acid sensors, including the transceptor mechanism, have implications for the pharmacological inhibition of mTORC1 and new therapeutic interventions.
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Affiliation(s)
| | - Deborah C. I. Goberdhan
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
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Gu CJ, Borjabad A, Hadas E, Kelschenbach J, Kim BH, Chao W, Arancio O, Suh J, Polsky B, McMillan J, Edagwa B, Gendelman HE, Potash MJ, Volsky DJ. EcoHIV infection of mice establishes latent viral reservoirs in T cells and active viral reservoirs in macrophages that are sufficient for induction of neurocognitive impairment. PLoS Pathog 2018; 14:e1007061. [PMID: 29879225 PMCID: PMC5991655 DOI: 10.1371/journal.ppat.1007061] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/29/2018] [Indexed: 02/06/2023] Open
Abstract
Suppression of HIV replication by antiretroviral therapy (ART) or host immunity can prevent AIDS but not other HIV-associated conditions including neurocognitive impairment (HIV-NCI). Pathogenesis in HIV-suppressed individuals has been attributed to reservoirs of latent-inducible virus in resting CD4+ T cells. Macrophages are persistently infected with HIV but their role as HIV reservoirs in vivo has not been fully explored. Here we show that infection of conventional mice with chimeric HIV, EcoHIV, reproduces physiological conditions for development of disease in people on ART including immunocompetence, stable suppression of HIV replication, persistence of integrated, replication-competent HIV in T cells and macrophages, and manifestation of learning and memory deficits in behavioral tests, termed here murine HIV-NCI. EcoHIV established latent reservoirs in CD4+ T lymphocytes in chronically-infected mice but could be induced by epigenetic modulators ex vivo and in mice. In contrast, macrophages expressed EcoHIV constitutively in mice for up to 16 months; murine leukemia virus (MLV), the donor of gp80 envelope in EcoHIV, did not infect macrophages. Both EcoHIV and MLV were found in brain tissue of infected mice but only EcoHIV induced NCI. Murine HIV-NCI was prevented by antiretroviral prophylaxis but once established neither persistent EcoHIV infection in mice nor NCI could be reversed by long-acting antiretroviral therapy. EcoHIV-infected, athymic mice were more permissive to virus replication in macrophages than were wild-type mice, suffered cognitive dysfunction, as well as increased numbers of monocytes and macrophages infiltrating the brain. Our results suggest an important role of HIV expressing macrophages in HIV neuropathogenesis in hosts with suppressed HIV replication.
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Affiliation(s)
- Chao-Jiang Gu
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Alejandra Borjabad
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Eran Hadas
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Jennifer Kelschenbach
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Boe-Hyun Kim
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Wei Chao
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Ottavio Arancio
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York, United States of America
| | - Jin Suh
- Department of Medicine, St. Joseph’s Regional Medical Center, Paterson, New Jersey, United States of America
| | - Bruce Polsky
- Department of Medicine, NYU Winthrop Hospital, Mineola, New York, United States of America
| | - JoEllyn McMillan
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Benson Edagwa
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Howard E. Gendelman
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Mary Jane Potash
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - David J. Volsky
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
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54
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Miska KB, Fetterer RH. The effect of Eimeria maxima infection on the expression of amino acid and sugar transporters aminopeptidase, as well as the di- and tri-peptide transporter PepT1, is not solely due to decreased feed intake. Poult Sci 2018; 97:1712-1721. [DOI: 10.3382/ps/pey015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 01/08/2018] [Indexed: 12/25/2022] Open
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Intracellular acidification reduces l-arginine transport via system y+L but not via system y+/CATs and nitric oxide synthase activity in human umbilical vein endothelial cells. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1192-1202. [DOI: 10.1016/j.bbadis.2018.01.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/15/2018] [Accepted: 01/31/2018] [Indexed: 12/13/2022]
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Sáez T, Salsoso R, Leiva A, Toledo F, de Vos P, Faas M, Sobrevia L. Human umbilical vein endothelium-derived exosomes play a role in foetoplacental endothelial dysfunction in gestational diabetes mellitus. Biochim Biophys Acta Mol Basis Dis 2018; 1864:499-508. [DOI: 10.1016/j.bbadis.2017.11.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 09/11/2017] [Accepted: 11/14/2017] [Indexed: 12/13/2022]
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Liu L, Zhang S, Bao J, He X, Tong D, Chen C, Ying Q, Zhang Q, Zhang C, Li J. Melatonin Improves Laying Performance by Enhancing Intestinal Amino Acids Transport in Hens. Front Endocrinol (Lausanne) 2018; 9:426. [PMID: 30105005 PMCID: PMC6077205 DOI: 10.3389/fendo.2018.00426] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/09/2018] [Indexed: 01/11/2023] Open
Abstract
The high concentration of melatonin (MEL) in the intestinal mucosa suggests that it has a special physiological function in intestine. In hens, previous studies have shown that MEL treatment promoted egg-laying performance. Considering the importance of amino acids (AA) for egg formation, we hypothesized that MEL may enhance the intestinal absorption of AA from the feed, thus promoting egg laying performance. In this study, we supplemented the hens with MEL for two consecutive weeks. The results showed that, compared with control group, feeding with 0.625 mg MEL/kg diets gave rise to higher egg laying rate (by 4.3%, P = 0.016), increased eggshell thickness (by 16.9%, P < 0.01) and albumen height (by 4.5%, P = 0.042). Meanwhile, feeding with 0.625 and 2.5 mg MEL/kg diets could significantly increase serum levels of aspartic acid, threonine, serine, glutamic acid, glycine, alanine, isoleucine, leucine, tyrosine, phenylalanine, lysine, histidine, arginine, and proline. Furthermore, a 0.625 mg MEL/kg diets could significantly increase the expression of PepT1 (by 3949.9%), B0AT (by 6045.9%), b0, +AT (by 603.5%), and EAAT3 (by 412.7%) in the jejunum. Additionally, in the cultured intestinal crypt "organoids," treatment with 0.5 μM MEL could significantly enhance the expression of PepT1, b0, +AT and EAAT3 mRNAs by 35.4%, 110.0%, and 160.1%, respectively. Detection of MEL concentration in serum and intestinal fluid suggested that lower dosage of MEL feeding was mainly acted on intestine locally, and further increased intestinal antioxidases (GPx-3, SOD-1 or PRDX-3) mRNA expression. Taken together, we demonstrated that MEL feeding in laying hens could locally promote the expression and function of AA transporter in small intestine by up-regulating antioxidases expression, and finally elevate laying performance.
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Affiliation(s)
- Lijuan Liu
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Siyu Zhang
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Jiayang Bao
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Xiaowen He
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Danni Tong
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Cong Chen
- Yanping Bureau of Animal Husbandry, Veterinary & Aquatic Products, Nanping, China
| | | | - Qing Zhang
- Yanping Bureau of Animal Husbandry, Veterinary & Aquatic Products, Nanping, China
| | - Caiqiao Zhang
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
- *Correspondence: Jian Li
| | - Jian Li
- Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
- Caiqiao Zhang
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58
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Subiabre M, Silva L, Villalobos-Labra R, Toledo F, Paublo M, López MA, Salsoso R, Pardo F, Leiva A, Sobrevia L. Maternal insulin therapy does not restore foetoplacental endothelial dysfunction in gestational diabetes mellitus. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2987-2998. [DOI: 10.1016/j.bbadis.2017.07.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/29/2017] [Accepted: 07/24/2017] [Indexed: 01/23/2023]
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59
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Kouis P, Hadjisavvas A, Middleton N, Papatheodorou SI, Kyriacou K, Yiallouros PK. The effect of l-Arginine on Ciliary Beat Frequency in PCD patients, non-PCD respiratory patients and healthy controls. Pulm Pharmacol Ther 2017; 48:15-21. [PMID: 29056509 DOI: 10.1016/j.pupt.2017.10.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 10/10/2017] [Accepted: 10/16/2017] [Indexed: 11/17/2022]
Abstract
OBJECTIVES Few studies have examined the potentially therapeutic effect of increasing the production of endogenous nitric oxide (NO) in Primary Ciliary Dyskinesia (PCD) and other chronic respiratory conditions. Nasal NO is low in PCD and has been found to correlate with compromised Ciliary Beat Frequency (CBF). In this study we assessed the effect of increasing l-Arginine, as the substrate of NO synthases, on CBF in biopsies of human respiratory ciliated epithelium. METHODOLOGY A total of 28 suspect cases with chronic respiratory manifestations referred for PCD diagnostic testing and 8 healthy controls underwent nasal brushing. Obtained epithelial cells were divided between three culture medium 199 solutions, containing different levels of l-Arginine (0.33 mM as baseline, 1 mM and 10 Mm as increased levels). CBF measurements were obtained at 37 °C and 25 °C at 1, 3 and 24 h after sample acquisition. RESULTS Among a total of 36 recruited subjects, 8 had PCD confirmed (PCD n = 8), 20 had PCD excluded (non-PCD n = 20) and 8 were healthy controls (Healthy Controls = 8). Among PCD subjects, ciliary motility was characterized by rotational (n = 5) or dyskinetic (n = 3) beating. At 37 °C, compared to baseline, higher levels of l-Arginine resulted in up to 9% CBF increase at 1 h (p = 0.007), up to 9% CBF increase at 3 h (p < 0.001) and up to 12% CBF increase at 24 h (p = 0.002). Similar although smaller scale increases were recorded at 25 °C. The effect of l-Arginine was time dependent (interaction p = 0.002) and was similar in PCD patients, non-PCD chronic respiratory patients and healthy controls (interaction p = 0.800). CONCLUSIONS l-Arginine increases CBF and merits to be evaluated as a potential stimulator of mucociliary clearance in chronic respiratory conditions and congenital ciliary disorders with residual motility. Larger human studies are needed to confirm these findings.
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Affiliation(s)
- Panayiotis Kouis
- Cyprus International Institute for Environmental & Public Health, Cyprus University of Technology, Limassol, Cyprus.
| | - Andreas Hadjisavvas
- Department of Electron Microscopy/Molecular Pathology, Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus; Cyprus School of Molecular Medicine, Nicosia, Cyprus.
| | - Nicos Middleton
- Department of Nursing, School of Health Sciences, Cyprus University of Technology, Limassol, Cyprus.
| | - Stefania I Papatheodorou
- Cyprus International Institute for Environmental & Public Health, Cyprus University of Technology, Limassol, Cyprus.
| | - Kyriacos Kyriacou
- Department of Electron Microscopy/Molecular Pathology, Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus; Cyprus School of Molecular Medicine, Nicosia, Cyprus.
| | - Panayiotis K Yiallouros
- Medical School, University of Cyprus, Nicosia, Cyprus; Hospital 'Archbishop Makarios III', Nicosia, Cyprus.
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Mandal A, Das S, Kumar A, Roy S, Verma S, Ghosh AK, Singh R, Abhishek K, Saini S, Sardar AH, Purkait B, Kumar A, Mandal C, Das P. l-Arginine Uptake by Cationic Amino Acid Transporter Promotes Intra-Macrophage Survival of Leishmania donovani by Enhancing Arginase-Mediated Polyamine Synthesis. Front Immunol 2017; 8:839. [PMID: 28798743 PMCID: PMC5526900 DOI: 10.3389/fimmu.2017.00839] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 07/03/2017] [Indexed: 11/24/2022] Open
Abstract
The survival of intracellular protozoan parasite, Leishmania donovani, the causative agent of Indian visceral leishmaniasis (VL), depends on the activation status of macrophages. l-Arginine, a semi-essential amino acid plays a crucial regulatory role for activation of macrophages. However, the role of l-arginine transport in VL still remains elusive. In this study, we demonstrated that intra-macrophage survival of L. donovani depends on the availability of extracellular l-arginine. Infection of THP-1-derived macrophage/human monocyte-derived macrophage (hMDM) with Leishmania, resulted in upregulation of l-arginine transport. While investigating the involvement of the transporters, we observed that Leishmania survival was greatly impaired when the transporters were blocked either using inhibitor or siRNA-mediated downregulation. CAT-2 was found to be the main isoform associated with l-arginine transport in L. donovani-infected macrophages. l-arginine availability and its transport regulated the host arginase in Leishmania infection. Arginase and inducible nitric oxide synthase (iNOS) expression were reciprocally regulated when assayed using specific inhibitors and siRNA-mediated downregulation. Interestingly, induction of iNOS expression and nitric oxide production were observed in case of inhibition of arginase in infected macrophages. Furthermore, inhibition of l-arginine transport as well as arginase resulted in decreased polyamine production, limiting parasite survival inside macrophages. l-arginine availability and transport regulated Th1/Th2 cytokine levels in case of Leishmania infection. Upregulation of l-arginine transport, induction of host arginase, and enhanced polyamine production were correlated with increased level of IL-10 and decreased level of IL-12 and TNF-α in L. donovani-infected macrophages. Our findings provide clear evidence for targeting the metabolism of l-arginine and l-arginine-metabolizing enzymes as an important therapeutic and prophylactic strategy to treat VL.
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Affiliation(s)
- Abhishek Mandal
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Sushmita Das
- Department of Microbiology, All India Institute of Medical Sciences (AIIMS), Patna, India
| | - Ajay Kumar
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Saptarshi Roy
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Sudha Verma
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Ayan Kumar Ghosh
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Ruby Singh
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Kumar Abhishek
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Savita Saini
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India.,Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Hajipur, India
| | - Abul Hasan Sardar
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Bidyut Purkait
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Ashish Kumar
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
| | - Chitra Mandal
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Pradeep Das
- Department of Molecular Biology, Rajendra Memorial Research Institute of Medical Sciences (ICMR), Patna, India
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Silva L, Subiabre M, Araos J, Sáez T, Salsoso R, Pardo F, Leiva A, San Martín R, Toledo F, Sobrevia L. Insulin/adenosine axis linked signalling. Mol Aspects Med 2017; 55:45-61. [DOI: 10.1016/j.mam.2016.11.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 11/16/2016] [Accepted: 11/17/2016] [Indexed: 12/22/2022]
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Lee KE, Kang YS. Characteristics of L-citrulline transport through blood-brain barrier in the brain capillary endothelial cell line (TR-BBB cells). J Biomed Sci 2017; 24:28. [PMID: 28490336 PMCID: PMC5424428 DOI: 10.1186/s12929-017-0336-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/03/2017] [Indexed: 12/04/2022] Open
Abstract
Background L-Citrulline is a neutral amino acid and a major precursor of L-arginine in the nitric oxide (NO) cycle. Recently it has been reported that L-citrulline prevents neuronal cell death and protects cerebrovascular injury, therefore, L-citrulline may have a neuroprotective effect to improve cerebrovascular dysfunction. Therefore, we aimed to clarify the brain transport mechanism of L-citrulline through blood-brain barrier (BBB) using the conditionally immortalized rat brain capillary endothelial cell line (TR-BBB cells), as an in vitro model of the BBB. Methods The uptake study of [14C] L-citrulline, quantitative real-time polymerase chain reaction (PCR) analysis, and rLAT1, system b0,+, and CAT1 small interfering RNA study were performed in TR-BBB cells. Results The uptake of [14C] L-citrulline was a time-dependent, but ion-independent manner in TR-BBB cells. The transport process involved two saturable components with a Michaelis–Menten constant of 30.9 ± 1.0 μM (Km1) and 1.69 ± 0.43 mM (Km2). The uptake of [14C] L-citrulline in TR-BBB cells was significantly inhibited by neutral and cationic amino acids, but not by anionic amino acids. In addition, [14C]L-citrulline uptake in the cells was markedly inhibited by 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH), which is the inhibitor of the large neutral amino acid transporter 1 (LAT1), B0, B0,+ and harmaline, the inhibitor of system b0,+. Gabapentin and L-dopa as the substrates of LAT1 competitively inhibited the uptake of [14C] L-citrulline. IC50 values for L-dopa, gabapentin, L-phenylalanine and L-arginine were 501 μM, 223 μM, 68.9 μM and 33.4 mM, respectively. The expression of mRNA for LAT1 was predominantly increased 187-fold in comparison with that of system b0,+ in TR-BBB cells. In the studies of LAT1, system b0,+ and CAT1 knockdown via siRNA transfection into TR-BBB cells, the transcript level of LAT1 and [14C] L-citrulline uptake by LAT1 siRNA were significantly reduced compared with those by control siRNA in TR-BBB cells. Conclusions Our results suggest that transport of L-citrulline is mainly mediated by LAT1 in TR-BBB cells. Delivery strategy for LAT1-mediated transport and supply of L-citrulline to the brain may serve as therapeutic approaches to improve its neuroprotective effect in patients with cerebrovascular disease.
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Affiliation(s)
- Kyeong-Eun Lee
- College of Pharmacy and Research Center for Cell Fate Control, Sookmyung Women's University, 52, Hyochangwon-gil, Yongsan-gu, Seoul, 140-742, South Korea
| | - Young-Sook Kang
- College of Pharmacy and Research Center for Cell Fate Control, Sookmyung Women's University, 52, Hyochangwon-gil, Yongsan-gu, Seoul, 140-742, South Korea.
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Yang G, Chu PL, Rump LC, Le TH, Stegbauer J. ACE2 and the Homolog Collectrin in the Modulation of Nitric Oxide and Oxidative Stress in Blood Pressure Homeostasis and Vascular Injury. Antioxid Redox Signal 2017; 26:645-659. [PMID: 27889958 DOI: 10.1089/ars.2016.6950] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Hypertension is the leading risk factor causing mortality and morbidity worldwide. Angiotensin (Ang) II, the most active metabolite of the renin-angiotensin system, plays an outstanding role in the pathogenesis of hypertension and vascular injury. Activation of angiotensin converting enzyme 2 (ACE2) has shown to attenuate devastating effects of Ang II in the cardiovascular system by reducing Ang II degradation and increasing Ang-(1-7) generation leading to Mas receptor activation. Recent Advances: Activation of the ACE2/Ang-(1-7)/Mas receptor axis reduces hypertension and improves vascular injury mainly through an increased nitric oxide (NO) bioavailability and decreased reactive oxygen species production. Recent studies reported that shedding of the enzymatically active ectodomain of ACE2 from the cell surface seems to regulate its activity and serves as an interorgan communicator in cardiovascular disease. In addition, collectrin, an ACE2 homolog with no catalytic activity, regulates blood pressure through an NO-dependent mechanism. CRITICAL ISSUES Large body of experimental data confirmed sustained beneficial effects of ACE2/Ang-(1-7)/Mas receptor axis activation on hypertension and vascular injury. Experimental studies also suggest that activation of collectrin might be beneficial in hypertension and endothelial dysfunction. Their role in clinical hypertension is unclear as selective and reliable activators of both axes are not yet available. FUTURE DIRECTIONS This review will highlight the results of recent research progress that illustrate the role of both ACE and collectrin in the modulation of NO and oxidative stress in blood pressure homeostasis and vascular injury, providing evidence for the potential therapeutic application of ACE2 and collectrin in hypertension and vascular disease. Antioxid. Redox Signal. 26, 645-659.
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Affiliation(s)
- Guang Yang
- 1 Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf , Düsseldorf, Germany
| | - Pei-Lun Chu
- 2 Division of Nephrology, Department of Medicine, University of Virginia , Charlottesville, Virginia.,3 Department of Internal Medicine, Graduate Institute of Biomedical and Pharmaceutical Science, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Lars C Rump
- 1 Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf , Düsseldorf, Germany
| | - Thu H Le
- 2 Division of Nephrology, Department of Medicine, University of Virginia , Charlottesville, Virginia
| | - Johannes Stegbauer
- 1 Department of Nephrology, Medical Faculty, Heinrich-Heine University Düsseldorf , Düsseldorf, Germany
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Celis N, Araos J, Sanhueza C, Toledo F, Beltrán AR, Pardo F, Leiva A, Ramírez MA, Sobrevia L. Intracellular acidification increases adenosine transport in human umbilical vein endothelial cells. Placenta 2017; 51:10-17. [DOI: 10.1016/j.placenta.2017.01.120] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/01/2017] [Accepted: 01/14/2017] [Indexed: 12/16/2022]
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65
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Weiler A, Volkenhoff A, Hertenstein H, Schirmeier S. Metabolite transport across the mammalian and insect brain diffusion barriers. Neurobiol Dis 2017; 107:15-31. [PMID: 28237316 DOI: 10.1016/j.nbd.2017.02.008] [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: 04/22/2016] [Revised: 01/02/2017] [Accepted: 02/20/2017] [Indexed: 12/31/2022] Open
Abstract
The nervous system in higher vertebrates is separated from the circulation by a layer of specialized endothelial cells. It protects the sensitive neurons from harmful blood-derived substances, high and fluctuating ion concentrations, xenobiotics or even pathogens. To this end, the brain endothelial cells and their interlinking tight junctions build an efficient diffusion barrier. A structurally analogous diffusion barrier exists in insects, where glial cell layers separate the hemolymph from the neural cells. Both types of diffusion barriers, of course, also prevent influx of metabolites from the circulation. Because neuronal function consumes vast amounts of energy and necessitates influx of diverse substrates and metabolites, tightly regulated transport systems must ensure a constant metabolite supply. Here, we review the current knowledge about transport systems that carry key metabolites, amino acids, lipids and carbohydrates into the vertebrate and Drosophila brain and how this transport is regulated. Blood-brain and hemolymph-brain transport functions are conserved and we can thus use a simple, genetically accessible model system to learn more about features and dynamics of metabolite transport into the brain.
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Affiliation(s)
- Astrid Weiler
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Badestr. 9, 48149 Münster, Germany
| | - Anne Volkenhoff
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Badestr. 9, 48149 Münster, Germany
| | - Helen Hertenstein
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Badestr. 9, 48149 Münster, Germany
| | - Stefanie Schirmeier
- Institut für Neuro- und Verhaltensbiologie, Universität Münster, Badestr. 9, 48149 Münster, Germany.
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66
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Miska K, Fetterer R. The mRNA expression of amino acid and sugar transporters, aminopeptidase, as well as the di- and tri-peptide transporter PepT1 in the intestines of Eimeria infected broiler chickens. Poult Sci 2017; 96:465-473. [DOI: 10.3382/ps/pew303] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 05/20/2016] [Accepted: 07/25/2016] [Indexed: 01/12/2023] Open
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Ramachandran J, Peluffo RD. Threshold levels of extracellular l-arginine that trigger NOS-mediated ROS/RNS production in cardiac ventricular myocytes. Am J Physiol Cell Physiol 2016; 312:C144-C154. [PMID: 27903582 DOI: 10.1152/ajpcell.00150.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 11/14/2016] [Accepted: 11/17/2016] [Indexed: 12/19/2022]
Abstract
l-Arginine (L-Arg) is the substrate for nitric oxide synthase (NOS) to produce nitric oxide (NO), a signaling molecule that is key in cardiovascular physiology and pathology. In cardiac myocytes, L-Arg is incorporated from the circulation through the functioning of system-y+ cationic amino acid transporters. Depletion of L-Arg leads to NOS uncoupling, with O2 rather than L-Arg as the terminal electron acceptor, resulting in superoxide formation. The reactive oxygen species (ROS) superoxide (O2˙-), combined with NO, may lead to the production of the reactive nitrogen species (RNS) peroxynitrite (ONOO-), which is recognized as a major contributor to myocardial depression. In this study we aimed to determine the levels of external L-Arg that trigger ROS/RNS production in cardiac myocytes. To this goal, we used a two-step experimental design in which acutely isolated cardiomyocytes were loaded with the dye coelenterazine that greatly increases its fluorescence quantum yield in the presence of ONOO- and O2˙- Cells were then exposed to different concentrations of extracellular L-Arg and changes in fluorescence were followed spectrofluorometrically. It was found that below a threshold value of ~100 µM, decreasing concentrations of L-Arg progressively increased ONOO-/ O2˙--induced fluorescence, an effect that was not mimicked by d-arginine or l-lysine and was fully blocked by the NOS inhibitor l-NAME. These results can be explained by NOS aberrant enzymatic activity and provide an estimate for the levels of circulating L-Arg below which ROS/RNS-mediated harmful effects arise in cardiac muscle.
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Affiliation(s)
- Jayalakshmi Ramachandran
- Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical and Health Sciences, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey
| | - R Daniel Peluffo
- Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical and Health Sciences, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, New Jersey
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68
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Gao C, Yang J, Chen M, Yan H, Wang X. Growth curves and age-related changes in carcass characteristics, organs, serum parameters, and intestinal transporter gene expression in domestic pigeon (Columba livia). Poult Sci 2016; 95:867-77. [DOI: 10.3382/ps/pev443] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 11/12/2015] [Indexed: 11/20/2022] Open
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69
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Dubó S, Gallegos D, Cabrera L, Sobrevia L, Zúñiga L, González M. Cardiovascular Action of Insulin in Health and Disease: Endothelial L-Arginine Transport and Cardiac Voltage-Dependent Potassium Channels. Front Physiol 2016; 7:74. [PMID: 27014078 PMCID: PMC4791397 DOI: 10.3389/fphys.2016.00074] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 02/15/2016] [Indexed: 12/19/2022] Open
Abstract
Impairment of insulin signaling on diabetes mellitus has been related to cardiovascular dysfunction, heart failure, and sudden death. In human endothelium, cationic amino acid transporter 1 (hCAT-1) is related to the synthesis of nitric oxide (NO) and insulin has a vascular effect in endothelial cells through a signaling pathway that involves increases in hCAT-1 expression and L-arginine transport. This mechanism is disrupted in diabetes, a phenomenon potentiated by excessive accumulation of reactive oxygen species (ROS), which contribute to lower availability of NO and endothelial dysfunction. On the other hand, electrical remodeling in cardiomyocytes is considered a key factor in heart failure progression associated to diabetes mellitus. This generates a challenge to understand the specific role of insulin and the pathways involved in cardiac function. Studies on isolated mammalian cardiomyocytes have shown prolongated action potential in ventricular repolarization phase that produces a long QT interval, which is well explained by attenuation in the repolarizing potassium currents in cardiac ventricles. Impaired insulin signaling causes specific changes in these currents, such a decrease amplitude of the transient outward K(+) (Ito) and the ultra-rapid delayed rectifier (IKur) currents where, together, a reduction of mRNA and protein expression levels of α-subunits (Ito, fast; Kv 4.2 and IKs; Kv 1.5) or β-subunits (KChIP2 and MiRP) of K(+) channels involved in these currents in a MAPK mediated pathway process have been described. These results support the hypothesis that lack of insulin signaling can produce an abnormal repolarization in cardiomyocytes. Furthermore, the arrhythmogenic potential due to reduced Ito current can contribute to an increase in the incidence of sudden death in heart failure. This review aims to show, based on pathophysiological models, the regulatory function that would have insulin in vascular system and in cardiac electrophysiology.
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Affiliation(s)
- Sebastián Dubó
- Department of Kinesiology, Faculty of Medicine, Universidad de Concepción Concepción, Chile
| | - David Gallegos
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Lissette Cabrera
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Department of Morphophysiology, Faculty of Medicine, Universidad Diego PortalesSantiago, Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynecology, Faculty of Medicine, School of Medicine, Pontificia Universidad Católica de ChileSantiago, Chile; Department of Physiology, Faculty of Pharmacy, Universidad de SevillaSeville, Spain; Faculty of Medicine and Biomedical Sciences, University of Queensland Centre for Clinical Research (UQCCR), University of QueenslandHerston, QLD, Queensland, Australia
| | - Leandro Zúñiga
- Centro de Investigaciones Médicas, Escuela de Medicina, Universidad de Talca Talca, Chile
| | - Marcelo González
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Group of Research and Innovation in Vascular Health (GRIVAS-Health)Chillán, Chile
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70
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Saylor D, Dickens AM, Sacktor N, Haughey N, Slusher B, Pletnikov M, Mankowski JL, Brown A, Volsky DJ, McArthur JC. HIV-associated neurocognitive disorder--pathogenesis and prospects for treatment. Nat Rev Neurol 2016; 12:234-48. [PMID: 26965674 DOI: 10.1038/nrneurol.2016.27] [Citation(s) in RCA: 560] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In the past two decades, several advancements have improved the care of HIV-infected individuals. Most importantly, the development and deployment of combination antiretroviral therapy (CART) has resulted in a dramatic decline in the rate of deaths from AIDS, so that people living with HIV today have nearly normal life expectancies if treated with CART. The term HIV-associated neurocognitive disorder (HAND) has been used to describe the spectrum of neurocognitive dysfunction associated with HIV infection. HIV can enter the CNS during early stages of infection, and persistent CNS HIV infection and inflammation probably contribute to the development of HAND. The brain can subsequently serve as a sanctuary for ongoing HIV replication, even when systemic viral suppression has been achieved. HAND can remain in patients treated with CART, and its effects on survival, quality of life and everyday functioning make it an important unresolved issue. In this Review, we describe the epidemiology of HAND, the evolving concepts of its neuropathogenesis, novel insights from animal models, and new approaches to treatment. We also discuss how inflammation is sustained in chronic HIV infection. Moreover, we suggest that adjunctive therapies--treatments targeting CNS inflammation and other metabolic processes, including glutamate homeostasis, lipid and energy metabolism--are needed to reverse or improve HAND-related neurological dysfunction.
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Affiliation(s)
- Deanna Saylor
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Alex M Dickens
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Ned Sacktor
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Norman Haughey
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Barbara Slusher
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Mikhail Pletnikov
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Joseph L Mankowski
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - Amanda Brown
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
| | - David J Volsky
- The Icahn School of Medicine at Mount Sinai, 1468 Madison Avenue, New York, New York 10029, USA
| | - Justin C McArthur
- Department of Neurology, Johns Hopkins University School of Medicine, Meyer 6113, 600 N Wolfe St, Baltimore, Maryland 21287, USA
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71
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Guzmán-Gutiérrez E, Armella A, Toledo F, Pardo F, Leiva A, Sobrevia L. Insulin requires A1 adenosine receptors expression to reverse gestational diabetes-increased L-arginine transport in human umbilical vein endothelium. Purinergic Signal 2015; 12:175-90. [PMID: 26710791 DOI: 10.1007/s11302-015-9491-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/17/2015] [Indexed: 01/06/2023] Open
Abstract
Gestational diabetes mellitus (GDM) associates with increased L-arginine transport and extracellular concentration of adenosine in human umbilical vein endothelial cells (HUVECs). In this study we aim to determine whether insulin reverses GDM-increased L-arginine transport requiring adenosine receptors expression in HUVECs. Primary cultured HUVECs from full-term normal (n = 38) and diet-treated GDM (n = 38) pregnancies were used. Insulin effect was assayed on human cationic amino acid transporter 1 (hCAT1) expression (protein, mRNA, SLC7A1 promoter activity) and activity (initial rates of L-arginine transport) in the absence or presence of adenosine receptors agonists or antagonists. A1 adenosine receptors (A1AR) and A2AAR expression (Western blot, quantitative PCR) was determined. Experiments were done in cells expressing or siRNA-suppressed expression of A1AR or A2AAR. HUVECs from GDM exhibit higher maximal transport capacity (maximal velocity (V max)/apparent Michaelis Menten constant (K m), V max/K m), which is blocked by insulin by reducing the V max to values in cells from normal pregnancies. Insulin also reversed the GDM-associated increase in hCAT-1 protein abundance and mRNA expression, and SLC7A1 promoter activity for the fragment -606 bp from the transcription start point. Insulin effects required A1AR, but not A2AAR expression and activity in this cell type. In the absence of insulin, GDM-increased hCAT-1 expression and activity required A2AAR expression and activity. HUVECs from GDM pregnancies exhibit a differential requirement of A1AR or A2AAR depending on the level of insulin, a phenomenon that represent a condition where adenosine or analogues of this nucleoside could be acting as helpers of insulin biological effects in GDM.
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Affiliation(s)
- Enrique Guzmán-Gutiérrez
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile.,Faculty of Health Sciences, Universidad San Sebastián, Concepción, 4080871, Chile
| | - Axel Armella
- Faculty of Health Sciences, Universidad San Sebastián, Concepción, 4080871, Chile
| | - Fernando Toledo
- Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, 3780000, Chile
| | - Fabián Pardo
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile
| | - Andrea Leiva
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, P.O. Box 114-D, Santiago, 8330024, Chile. .,Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville, E-41012, Spain. .,University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, QLD, 4029, Australia.
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72
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Zhang H, Gilbert ER, Zhang K, Ding X, Luo Y, Wang J, Zeng Q, Bai S. Uptake of manganese from manganese-lysine complex in the primary rat intestinal epithelial cells. J Anim Physiol Anim Nutr (Berl) 2015; 101:147-158. [DOI: 10.1111/jpn.12430] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 09/30/2015] [Indexed: 11/30/2022]
Affiliation(s)
- H. Zhang
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
| | - E. R. Gilbert
- Department of Animal and Poultry Sciences; Virginia Tech University; Blacksburg VA USA
| | - K. Zhang
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
| | - X. Ding
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
| | - Y. Luo
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
| | - J. Wang
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
| | - Q. Zeng
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
| | - S. Bai
- Animal Nutrition Institute; Sichuan Agricultural University Ya'an; Sichuan China
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Burrows GG, Van't Hof W, Reddy AP, Wilmarth PA, David LL, Raber A, Bogaerts A, Timmerman L, Pinxteren J, Roobrouck VD, Deans RJ, Maziarz RT. Solution-Phase Crosstalk and Regulatory Interactions Between Multipotent Adult Progenitor Cells and Peripheral Blood Mononuclear Cells. Stem Cells Transl Med 2015; 4:1436-49. [PMID: 26494783 PMCID: PMC4675500 DOI: 10.5966/sctm.2014-0225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Accepted: 08/03/2015] [Indexed: 02/06/2023] Open
Abstract
UNLABELLED Multipotent adult progenitor cells (MAPCs) are adult adherent stromal stem cells currently being assessed in clinical trials for acute graft versus host disease with demonstrated immunomodulatory capabilities and the potential to ameliorate detrimental autoimmune and inflammation-related processes. Anti-CD3/anti-CD28 (3/28) activation of T cells within the peripheral blood mononuclear cell (PBMC) compartment was performed in the presence or absence of MAPCs. Liquid chromatography-coupled tandem mass spectrometry was used to characterize the differential secretion of proteins, and transcriptional profiling was used to monitor mRNA expression changes in both cell populations. Overall, 239 secreted and/or ectodomain-shed proteins were detected in the secretomes of PBMCs and MAPCs. In addition, 3/28 activation of PBMCs induced differential expression of 2,925 genes, and 22% of these transcripts were differentially expressed on exposure to MAPCs in Transwell. MAPCs exposed to 3/28-activated PBMCs showed differential expression of 1,247 MAPC genes. Crosstalk was demonstrated by reciprocal transcriptional regulation. Secretome proteins and transcriptional signatures were used to predict molecular activities by which MAPCs could dampen local and systemic inflammatory responses. These data support the hypothesis that MAPCs block PBMC proliferation via cell cycle arrest coupled to metabolic stress in the form of tryptophan depletion, resulting in GCN2 kinase activation, downstream signaling, and inhibition of cyclin D1 translation. These data also provide a plausible explanation for the immune privilege reported with administration of donor MAPCs. Although most components of the major histocompatibility complex class II antigen presentation pathway were markedly transcriptionally upregulated, cell surface expression of human leukocyte antigen-DR is minimal on MAPCs exposed to 3/28-activated PBMCs. SIGNIFICANCE This study documents experiments quantifying solution-phase crosstalk between multipotent adult progenitor cells (MAPCs) and peripheral blood mononuclear cells. The secretome and transcriptional changes quantified suggest mechanisms by which MAPCs are hypothesized to provide both local and systemic immunoregulation of inflammation. The potential impact of these studies includes development of a robust experimental framework to be used for preclinical evaluation of the specific mechanisms by which beneficial effects are obtained after treatment of patients with MAPCs.
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Affiliation(s)
- Gregory G Burrows
- Center for Hematologic Malignancies, Division of Hematology and Medical Oncology, Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA Department of Neurology, Oregon Health and Science University, Portland, Oregon, USA Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon, USA
| | - Wouter Van't Hof
- Regenerative Medicine Program, Athersys Inc., Cleveland, Ohio, USA National Center for Regenerative Medicine, Cleveland, Ohio, USA
| | - Ashok P Reddy
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon, USA
| | - Phillip A Wilmarth
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon, USA
| | - Larry L David
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon, USA
| | - Amy Raber
- Regenerative Medicine Program, Athersys Inc., Cleveland, Ohio, USA
| | | | | | | | | | - Robert J Deans
- Regenerative Medicine Program, Athersys Inc., Cleveland, Ohio, USA National Center for Regenerative Medicine, Cleveland, Ohio, USA ReGenesys, Inc., Leuven, Belgium
| | - Richard T Maziarz
- Center for Hematologic Malignancies, Division of Hematology and Medical Oncology, Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA
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74
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Ingoglia F, Visigalli R, Rotoli BM, Barilli A, Riccardi B, Puccini P, Dall'Asta V. Functional activity of L-carnitine transporters in human airway epithelial cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1858:210-9. [PMID: 26607009 DOI: 10.1016/j.bbamem.2015.11.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/21/2015] [Accepted: 11/18/2015] [Indexed: 12/30/2022]
Abstract
Carnitine plays a physiologically important role in the β-oxidation of fatty acids, facilitating the transport of long-chain fatty acids across the inner mitochondrial membrane. Distribution of carnitine within the body tissues is mainly performed by novel organic cation transporter (OCTN) family, including the isoforms OCTN1 (SLC22A4) and OCTN2 (SLC22A5) expressed in human. We performed here a characterization of carnitine transport in human airway epithelial cells A549, Calu-3, NCl-H441, and BEAS-2B, by means of an integrated approach combining data of mRNA/protein expression with the kinetic and inhibition analyses of L-[(3)H]carnitine transport. Carnitine uptake was strictly Na(+)-dependent in all cell models. In A549 and BEAS-2B cells, carnitine uptake was mediated by one high-affinity component (Km<2 μM) identifiable with OCTN2. In both these cell models, indeed, carnitine uptake was maximally inhibited by betaine and strongly reduced by SLC22A5/OCTN2 silencing. Conversely, Calu-3 and NCl-H441 exhibited both a high (Km~20 μM) and a low affinity (Km>1 mM) transport component. While the high affinity component is identifiable with OCTN2, the low affinity uptake is mediated by ATB(0,+), a Na(+), and Cl(-)-coupled transport system for neutral and cationic amino acids, as demonstrated by the inhibition by leucine and arginine, as well as by SLC6A14/ATB(0,+) silencing. The presence of this transporter leads to a massive accumulation of carnitine inside the cells and may be of peculiar relevance in pathologic conditions of carnitine deficiency, such as those associated to OCTN2 defects.
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Affiliation(s)
- Filippo Ingoglia
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Rossana Visigalli
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Bianca Maria Rotoli
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Amelia Barilli
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Benedetta Riccardi
- Preclinical Pharmacokinetics, Biochemistry & Metabolism Dept., Chiesi Farmaceutici, Largo F. Belloli 11/A, 43122 Parma, Italy
| | - Paola Puccini
- Preclinical Pharmacokinetics, Biochemistry & Metabolism Dept., Chiesi Farmaceutici, Largo F. Belloli 11/A, 43122 Parma, Italy
| | - Valeria Dall'Asta
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy.
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Zielińska M, Milewski K, Skowrońska M, Gajos A, Ziemińska E, Beręsewicz A, Albrecht J. Induction of inducible nitric oxide synthase expression in ammonia-exposed cultured astrocytes is coupled to increased arginine transport by upregulated y(+)LAT2 transporter. J Neurochem 2015; 135:1272-81. [PMID: 26448619 DOI: 10.1111/jnc.13387] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 09/10/2015] [Accepted: 09/25/2015] [Indexed: 12/17/2022]
Abstract
One of the aspects of ammonia toxicity to brain cells is increased production of nitric oxide (NO) by NO synthases (NOSs). Previously we showed that ammonia increases arginine (Arg) uptake in cultured rat cortical astrocytes specifically via y(+)L amino acid transport system, by activation of its member, a heteromeric y(+)LAT2 transporter. Here, we tested the hypothesis that up-regulation of y(+)LAT2 underlies ammonia-dependent increase of NO production via inducible NOS (iNOS) induction, and protein nitration. Treatment of rat cortical astrocytes for 48 with 5 mM ammonium chloride ('ammonia') (i) increased the y(+)L-mediated Arg uptake, (ii) raised the expression of iNOS and endothelial NOS (eNOS), (iii) stimulated NO production, as manifested by increased nitrite+nitrate (Griess) and/or nitrite alone (chemiluminescence), and consequently, (iv) evoked nitration of tyrosine residues of proteins in astrocytes. Except for the increase of eNOS, all the above described effects of ammonia were abrogated by pre-treatment of astrocytes with either siRNA silencing of the Slc7a6 gene coding for y(+)LAT2 protein, or antibody to y(+)LAT2, indicating their strict coupling to y(+)LAT2 activity. Moreover, induction of y(+)LAT2 expression by ammonia was sensitive to Nf-κB inhibitor, BAY 11-7085, linking y(+)LAT2 upregulation to the Nf-κB activation in this experimental setting as reported earlier and here confirmed. Importantly, ammonia did not affect y(+)LAT2 expression nor y(+)L-mediated Arg uptake activity in the cultured cerebellar neurons, suggesting astroglia-specificity of the above described mechanism. The described coupling of up-regulation of y(+)LAT2 transporter with iNOS in ammonia-exposed astrocytes may be considered as a mechanism to ensure NO supply for protein nitration. Ammonia (NH4(+)) increases the expression and activity of the L-arginine (Arg) transporter (Arg/neutral amino acids [NAA] exchanger) y(+)LAT2 in cultured rat cortical astrocytes by a mechanism involving activation (nuclear translocation) of the transcription factor nuclear factor-Nuclear factor-κB (Nf-κB-p65). Up-regulation of y(+)LAT2 transporter is coupled with increased inducible nitric oxide synthase (iNOS) expression, which leads to increase nitric oxide (NO) synthesis and protein nitration.
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Affiliation(s)
- Magdalena Zielińska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Krzysztof Milewski
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Marta Skowrońska
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Anna Gajos
- Medical Center of Postgraduate Education, Warsaw, Poland
| | - Elżbieta Ziemińska
- Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | | | - Jan Albrecht
- Department of Neurotoxicology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
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Cimen Bozkus C, Elzey BD, Crist SA, Ellies LG, Ratliff TL. Expression of Cationic Amino Acid Transporter 2 Is Required for Myeloid-Derived Suppressor Cell-Mediated Control of T Cell Immunity. THE JOURNAL OF IMMUNOLOGY 2015; 195:5237-50. [PMID: 26491198 DOI: 10.4049/jimmunol.1500959] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 09/24/2015] [Indexed: 01/04/2023]
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature cells that expand during benign and cancer-associated inflammation and are characterized by their ability to inhibit T cell immunity. Increased metabolism of l-Arginine (l-Arg), through the enzymes arginase 1 and NO synthase 2 (NOS2), is well documented as a major MDSC suppressive mechanism. Therefore, we hypothesized that restricting MDSC uptake of l-Arg is a critical control point to modulate their suppressor activity. Using murine models of prostate-specific inflammation and cancer, we have identified the mechanisms by which extracellular l-Arg is transported into MDSCs. We have shown that MDSCs recruited to localized inflammation and tumor sites upregulate cationic amino acid transporter 2 (Cat2), coordinately with Arg1 and Nos2. Cat2 expression is not induced in MDSCs in peripheral organs. CAT2 contributes to the transport of l-Arg in MDSCs and is an important regulator of MDSC suppressive function. MDSCs that lack CAT2 have significantly reduced suppressive ability ex vivo and display impaired capacity for regulating T cell responses in vivo as evidenced by increased T cell expansion and decreased tumor growth in Cat2(-/-) mice. The abrogation of suppressive function is due to low intracellular l-Arg levels, which leads to the impaired ability of NOS2 to catalyze l-Arg-dependent metabolic processes. Together, these findings demonstrate that CAT2 modulates MDSC function. In the absence of CAT2, MDSCs display diminished capacity for controlling T cell immunity in prostate inflammation and cancer models, where the loss of CAT2 results in enhanced antitumor activity.
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Affiliation(s)
- Cansu Cimen Bozkus
- Comparative Pathobiology Department, Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907; and
| | - Bennett D Elzey
- Comparative Pathobiology Department, Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907; and
| | - Scott A Crist
- Comparative Pathobiology Department, Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907; and
| | - Lesley G Ellies
- Department of Pathology, University of California, San Diego, La Jolla, CA 92093
| | - Timothy L Ratliff
- Comparative Pathobiology Department, Purdue University Center for Cancer Research, Purdue University, West Lafayette, IN 47907; and
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77
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Substrate specificity and transport mechanism of amino-acid transceptor Slimfast from Aedes aegypti. Nat Commun 2015; 6:8546. [PMID: 26449545 PMCID: PMC4608377 DOI: 10.1038/ncomms9546] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 09/03/2015] [Indexed: 12/11/2022] Open
Abstract
Anautogenous mosquitoes depend on vertebrate blood as nutrient source for their eggs. A highly efficient set of membrane transporters mediates the massive movement of nutrient amino acids between mosquito tissues after a blood meal. Here we report the characterization of the amino-acid transporter Slimfast (Slif) from the yellow-fever mosquito Aedes aegypti using codon-optimized heterologous expression. Slif is a well-known component of the target-of-rapamycin signalling pathway and fat body nutrient sensor, but its substrate specificity and transport mechanism were unknown. We found that Slif transports essential cationic and neutral amino acids with preference for arginine. It has an unusual dual-affinity mechanism with only the high affinity being Na+ dependent. Tissue-specific expression and blood meal-dependent regulation of Slif are consistent with conveyance of essential amino acids from gut to fat body. Slif represents a novel transport system and type of transceptor for sensing and transporting essential amino acids during mosquito reproduction. Anautogenous mosquitoes need to obtain essential amino acids from a blood meal for reproduction. Here, the authors examine the amino acid transporter Slimfast from the yellow-fever mosquito and describe both its specificity and mechanism of action.
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78
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Coughlin CR, van Karnebeek CDM, Al-Hertani W, Shuen AY, Jaggumantri S, Jack RM, Gaughan S, Burns C, Mirsky DM, Gallagher RC, Van Hove JLK. Triple therapy with pyridoxine, arginine supplementation and dietary lysine restriction in pyridoxine-dependent epilepsy: Neurodevelopmental outcome. Mol Genet Metab 2015; 116:35-43. [PMID: 26026794 DOI: 10.1016/j.ymgme.2015.05.011] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 05/22/2015] [Accepted: 05/22/2015] [Indexed: 11/21/2022]
Abstract
Pyridoxine-dependent epilepsy (PDE) is an epileptic encephalopathy characterized by response to pharmacologic doses of pyridoxine. PDE is caused by deficiency of α-aminoadipic semialdehyde dehydrogenase resulting in impaired lysine degradation and subsequent accumulation of α-aminoadipic semialdehyde. Despite adequate seizure control with pyridoxine monotherapy, 75% of individuals with PDE have significant developmental delay and intellectual disability. We describe a new combined therapeutic approach to reduce putative toxic metabolites from impaired lysine metabolism. This approach utilizes pyridoxine, a lysine-restricted diet to limit the substrate that leads to neurotoxic metabolite accumulation and L-arginine to compete for brain lysine influx and liver mitochondrial import. We report the developmental and biochemical outcome of six subjects who were treated with this triple therapy. Triple therapy reduced CSF, plasma, and urine biomarkers associated with neurotoxicity in PDE. The addition of arginine supplementation to children already treated with dietary lysine restriction and pyridoxine further reduced toxic metabolites, and in some subjects appeared to improve neurodevelopmental outcome. Dietary lysine restriction was associated with improved seizure control in one subject, and the addition of arginine supplementation increased the objective motor outcome scale in two twin siblings, illustrating the contribution of each component of this treatment combination. Optimal results were noted in the individual treated with triple therapy early in the course of the disease. Residual disease symptoms could be related to early injury suggested by initial MR imaging prior to initiation of treatment or from severe epilepsy prior to diagnosis. This observational study reports the use of triple therapy, which combines three effective components in this rare condition, and suggests that early diagnosis and treatment with this new triple therapy may ameliorate the cognitive impairment in PDE.
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Affiliation(s)
- Curtis R Coughlin
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, United States
| | - Clara D M van Karnebeek
- Division of Biochemical Diseases &Treatable Intellectual Disability Endeavour in British Columbia (TIDE-BC), Department of Pediatrics, BC Children's Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Walla Al-Hertani
- Department of Medical Genetics, Montreal Children's Hospital, McGill University of Health Centre, Montreal, QC, Canada
| | - Andrew Y Shuen
- Department of Medical Genetics, Montreal Children's Hospital, McGill University of Health Centre, Montreal, QC, Canada
| | - Sravan Jaggumantri
- Division of Biochemical Diseases &Treatable Intellectual Disability Endeavour in British Columbia (TIDE-BC), Department of Pediatrics, BC Children's Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Rhona M Jack
- Department of Laboratory Medicine, Seattle Children's Hospital Laboratory, Seattle, WA, United States
| | - Sommer Gaughan
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, United States
| | - Casey Burns
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, United States
| | - David M Mirsky
- Department of Radiology, University of Colorado, Aurora, CO, United States
| | - Renata C Gallagher
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, United States
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado, Aurora, CO, United States.
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79
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Henriques C, Miller MP, Catanho M, de Carvalho TMU, Krieger MA, Probst CM, de Souza W, Degrave W, Amara SG. Identification and functional characterization of a novel arginine/ornithine transporter, a member of a cationic amino acid transporter subfamily in the Trypanosoma cruzi genome. Parasit Vectors 2015; 8:346. [PMID: 26109388 PMCID: PMC4486710 DOI: 10.1186/s13071-015-0950-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 06/13/2015] [Indexed: 01/03/2023] Open
Abstract
Background Trypanosoma cruzi, the etiological agent of Chagas disease, is auxotrophic for arginine. It obtains this amino acid from the host through transporters expressed on the plasma membrane and on the membranes of intracellular compartments. A few cationic amino acid transporters have been characterized at the molecular level, such as the novel intracellular arginine/ornithine transporter, TcCAT1.1, a member of the TcCAT subfamily that is composed of four almost identical open reading frames in the T. cruzi genome. Methods The functional characterization of the TcCAT1.1 isoform was performed in two heterologous expression systems. TcCAT subfamily expression was evaluated by real-time PCR in polysomal RNA fractions, and the cellular localization of TcCAT1.1 fused to EGFP was performed by confocal and immunoelectron microscopy. Results In the S. cerevisiae expression system, TcCAT1.1 showed high affinity for arginine (Km = 0.085 ± 0.04 mM) and low affinity for ornithine (Km = 1.7 ± 0.2 mM). Xenopus laevis oocytes expressing TcCAT1.1 showed a 7-fold increase in arginine uptake when they were pre-loaded with arginine, indicating that transport is enhanced by substrates on the trans side of the membrane (trans-stimulation). Oocytes that were pre-loaded with [3H]-arginine displayed a 16-fold higher efflux of [3H]-arginine compared with that of the control. Analysis of polysomal RNA fractions demonstrated that the expression of members of the arginine transporter TcCAT subfamily is upregulated under nutritional stress and that this upregulation precedes metacyclogenesis. To investigate the cellular localization of the transporter, EGFP was fused to TcCAT1.1, and fluorescence microscopy and immunocytochemistry revealed the intracellular labeling of vesicles in the anterior region, in a network of tubules and vesicles. Conclusions TcCAT1.1 is a novel arginine/ornithine transporter, an exchanger expressed in intracellular compartments that is physiologically involved in arginine homeostasis throughout the T. cruzi life cycle. The properties and estimated kinetic parameters of TcCAT1.1 can be extended to other members of the TcCAT subfamily.
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Affiliation(s)
- Cristina Henriques
- Fundação Oswaldo Cruz, Fiocruz-Mato Grosso do Sul, Rua Gabriel Abrão 92-Jardim das Nações, Campo Grande, MS, 89081-746, Brazil. .,Instituto de Biofísica Carlos Chagas Filho-UFRJ, CCS-Bloco G-Laboratório de Ultraestrutura Celular Hertha Meyer, Rio de Janeiro, RJ, 21949-900, Brazil. .,Nucleo de Biologia Estrutural e Biomagens, Universidade Federal do Rio de Janeiro-CENABIO, Rio de Janeiro, RJ, Brazil.
| | - Megan P Miller
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15260, USA.
| | - Marcos Catanho
- Fiocruz, Instituto Oswaldo Cruz, Laboratório de Genômica Funcional e Bioinformática, Av. Brasil 4365, Manguinhos, 21040-900, Rio de Janeiro, RJ, Brazil.
| | - Técia Maria Ulisses de Carvalho
- Instituto de Biofísica Carlos Chagas Filho-UFRJ, CCS-Bloco G-Laboratório de Ultraestrutura Celular Hertha Meyer, Rio de Janeiro, RJ, 21949-900, Brazil.
| | | | | | - Wanderley de Souza
- Instituto de Biofísica Carlos Chagas Filho-UFRJ, CCS-Bloco G-Laboratório de Ultraestrutura Celular Hertha Meyer, Rio de Janeiro, RJ, 21949-900, Brazil. .,Nucleo de Biologia Estrutural e Biomagens, Universidade Federal do Rio de Janeiro-CENABIO, Rio de Janeiro, RJ, Brazil. .,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Biomagens-INBEB, Rio de Janeiro, Brazil.
| | - Wim Degrave
- Fiocruz, Instituto Oswaldo Cruz, Laboratório de Genômica Funcional e Bioinformática, Av. Brasil 4365, Manguinhos, 21040-900, Rio de Janeiro, RJ, Brazil.
| | - Susan Gaye Amara
- National Institute of Mental Health, NIH Building 10 Center Driver, Room 4N222, MSC 1381, Bethesda, MD, 20892-1381, USA. .,Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15260, USA.
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80
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Abstract
Collectrin (Tmem27) is a transmembrane glycoprotein that is highly expressed in the kidney and vascular endothelium. It is a homologue of the angiotensin-converting enzyme 2 (ACE2) but harbors no catalytic domain. In the extravascular tissues of the kidney, collectrin is localized to the proximal tubule and collecting duct. Collectrin-deficient mice are featured with hypertension and exaggerated salt sensitivity. These phenotypes are associated with impaired uptake of the nitric oxide precursor L-arginine and the expression of its amino acid transporters, CAT-1 and y(+)LAT1, in endothelial cells. In addition, collectrin-deficient mice display decreased dimerization of nitric oxide synthase and decreased nitric oxide synthesis, but enhanced superoxide generation, suggesting that deletion of collectrin leads to a state of nitric oxide synthase uncoupling. These findings suggest that collectrin plays a protective role against hypertension. The collectrin knockout mouse represents a unique model for hypertension research. Furthermore, collectrin may serve as a novel therapeutic target in the treatment of hypertension.
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81
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Miska KB, Fetterer RH, Wong EA. mRNA expression of amino acid transporters, aminopeptidase, and the di- and tri-peptide transporter PepT1 in the intestine and liver of posthatch broiler chicks. Poult Sci 2015; 94:1323-32. [PMID: 25825788 DOI: 10.3382/ps/pev059] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2014] [Indexed: 12/22/2022] Open
Abstract
Amino acid (AA) transporter proteins are responsible for the movement of amino acids in and out of cells. Aminopeptidase cleaves AAs from the N-terminus of polypeptides making them available for transport, while PepT1 is a di- and tripeptide transporter. In the intestine, these proteins are present on the brush border and basolateral membranes of enterocytes, and are essential for the uptake of AAs into enterocytes and their release into circulation. The purpose of this study was to determine the level of transcription of these genes after hatch in 3 regions of the small intestine, the ceca, and liver. Heritage broiler chicks (n=5) were sampled at day after hatch and days 3, 5, 7, 10, 12, 14, 17, and 21 posthatch, and mRNA expression level was measured using absolute quantitation. The small intestine (duodenum, jejunum, and ileum) expressed the largest quantities of each gene tested. The expression in the ceca and liver was 1 to 3 orders of magnitude less than that of the small intestine. The expression of basolateral transporters in the small intestine was more constant over days posthatch than the expression of brush border transporters. In the ceca the expression of the brush border transporters decreased over the sampling period, while expression of basolateral genes was relatively constant. In the liver the expression of Na+ independent cationic and zwitterionic amino acid transporter (bo,+AT), Na+ independent cationic amino acid transporter 2 (CAT2), excitatory amino acid transporter 3 (EAAT3), and the heavy chain corresponding to the bo,+) system (rBAT) significantly decreased at 12 days posthatch; however, the expression of Na+ independent cationic and Na+ dependent neutral amino acid transporter 1 (y+LAT1), Na+ coupled neutral amino acid transporter 1; (SNAT1), and Na+ coupled neutral amino acid transporter 2 (SNAT2) significantly increased at day 5 posthatch compared to day 1 and these levels remained throughout the rest of the sampling period. The current results suggest that at 1 day posthatch chicks are capable of AA processing and transport in the intestine as well as the liver. Additionally the ability of the ceca in transporting AA from the lumen may decrease with age. The liver should be capable of amino acid transport, but its capabilities may be more specific since the expression of several transporters in this organ is either absent or very low.
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Affiliation(s)
- Katarzyna B Miska
- Animal Bioscience and Biotechnology Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Beltsville, MD 20705
| | - Raymond H Fetterer
- Animal Parasitic Diseases Laboratory, Henry A. Wallace Beltsville Agricultural Research Center, Beltsville, MD 20705
| | - Eric A Wong
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA 24061
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82
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Liu L, Shen J, Zhao C, Wang X, Yao J, Gong Y, Yang X. Dietary Astragalus polysaccharide alleviated immunological stress in broilers exposed to lipopolysaccharide. Int J Biol Macromol 2015; 72:624-32. [DOI: 10.1016/j.ijbiomac.2014.08.057] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 07/26/2014] [Accepted: 08/27/2014] [Indexed: 01/08/2023]
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83
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Silva R, Carmo H, Vilas-Boas V, Barbosa DJ, Monteiro M, de Pinho PG, de Lourdes Bastos M, Remião F. Several transport systems contribute to the intestinal uptake of Paraquat, modulating its cytotoxic effects. Toxicol Lett 2015; 232:271-83. [DOI: 10.1016/j.toxlet.2014.10.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 10/09/2014] [Accepted: 10/09/2014] [Indexed: 11/29/2022]
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84
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Zhou J, Fan S, Cao Y, Zhu M, Han Y, Cao X, Li Y. Tumor necrosis factor-α suppresses the protein fractional synthesis rate of the small intestine stimulated by glutamine in rats. Exp Ther Med 2014; 9:547-552. [PMID: 25574232 PMCID: PMC4280961 DOI: 10.3892/etm.2014.2129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 10/21/2014] [Indexed: 12/21/2022] Open
Abstract
The objective of this study was to examine whether and how TNF-α affects glutamine-enhanced protein synthesis and the expression of the amino acid transporter ASCT2 in the small intestine at the mRNA and protein levels. A total of 30 male Sprague-Dawley rats were randomly assigned into three groups, namely the total parenteral nutrition (TPN; control), glutamine-treated (Gln), and glutamine- and tumor necrosis factor-α (TNF-α)-treated (TNF-α) groups. At 30 min prior to examination, all rats were mainlined with [L-15N]leucine. The concentration of TNF-α in plasma and of glutamine in plasma and the small intestine was measured. The fractional synthesis rate (FSR) of protein and the mRNA and protein expression levels of ASCT2 in the small intestine were assessed. The level of TNF-α was highest in the TNF-α group and the glutamine concentration was elevated to a greater extent in the TNF-α group than in the other two groups. However, the FSR of protein in the small intestine was significantly higher in the Gln group compared with that in the TNF-α group. The mRNA and protein expression levels of ASCT2 in the experimental groups were significantly higher that those in the control group, but did not differ significantly between the Gln and TNF-α groups. These results indicate that TNF-α may attenuate glutamine-stimulated protein synthesis in the small intestine in the early stage of sepsis in rats. The mechanism may be that TNF-α inhibits the function of the glutamine transporter in the uptake the glutamine into target cells for protein synthesis. This inhibition may occur at or following protein translation.
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Affiliation(s)
- Jihong Zhou
- Department of Burns and Plastic Surgery, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, P.R. China
| | - Shengxian Fan
- Department of General Surgery, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, P.R. China
| | - Yacheng Cao
- Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu 210002, P.R. China
| | - Mingfang Zhu
- Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu 210002, P.R. China
| | - Yong Han
- Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu 210002, P.R. China
| | - Xueying Cao
- Department of Burns and Plastic Surgery, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, P.R. China
| | - Yousheng Li
- Department of General Surgery, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, P.R. China
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85
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Orlando P, Silvestri S, Brugè F, Tiano L, Kloting I, Falcioni G, Polidori C. High-fat diet-induced met-hemoglobin formation in rats prone (WOKW) or resistant (DA) to the metabolic syndrome: effect of CoQ10 supplementation. Biofactors 2014; 40:603-9. [PMID: 25428841 DOI: 10.1002/biof.1190] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 10/18/2014] [Indexed: 01/19/2023]
Abstract
The aim of this study was to evaluate the effects of a high-fat diet (HFD) on oxidative indexes in WistarOttawaKarlsburg W (WOKW) rats used as a model of metabolic syndrome in comparison with Dark Agouti (DA) rats used as a control strain. This syndrome is defined by the occurrence of two or more risk factors including obesity, hypertension, dyslipidemia, and insulin resistance. Forty rats were used in the study and the effect of HFD was evaluated in terms of body weight and both hemoglobin and CoQ oxidative status. Moreover, 16 rats (8 of each strain) were supplemented with 3 mg/100 g b.w. of CoQ10 for 1 month in view of its beneficial properties in cardiovascular disease due to its antioxidant activity in the lipid environment. HFD promoted an increase in body weight, in particular in WOKW males, and in the methemoglobin (met-Hb) index in both strains. Moreover, HFD promoted endogenous CoQ10 oxidation. CoQ10 supplementation was able to efficiently counteract the HFD pro-oxidant effects, preventing met-Hb formation and CoQ oxidation.
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Affiliation(s)
- Patrick Orlando
- Department of Clinical and Dental Sciences, Polytechnic University of Marche, Ancona, Italy
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86
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Linking our understanding of mammary gland metabolism to amino acid nutrition. Amino Acids 2014; 46:2447-62. [DOI: 10.1007/s00726-014-1818-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 07/25/2014] [Indexed: 12/15/2022]
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87
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Miska KB, Fetterer RH, Wong EA. The mRNA expression of amino acid transporters, aminopeptidase N, and the di- and tri-peptide transporter PepT1 in the embryo of the domesticated chicken (Gallus gallus) shows developmental regulation. Poult Sci 2014; 93:2262-70. [DOI: 10.3382/ps.2014-03983] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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88
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Yu W, McConathy J, Olson JJ, Goodman MM. System a amino acid transport-targeted brain and systemic tumor PET imaging agents 2-amino-3-[(18)F]fluoro-2-methylpropanoic acid and 3-[(18)F]fluoro-2-methyl-2-(methylamino)propanoic acid. Nucl Med Biol 2014; 42:8-18. [PMID: 25263130 DOI: 10.1016/j.nucmedbio.2014.07.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 07/21/2014] [Accepted: 07/25/2014] [Indexed: 11/16/2022]
Abstract
INTRODUCTION Amino acid based radiotracers target tumor cells through increased uptake by membrane-associated amino acid transport (AAT) systems. In the present study, four structurally related non-natural (18)F-labeled amino acids, (R)- and (S)-[(18)F]FAMP 1 and (R)- and (S)-[(18)F]MeFAMP 2 have been prepared and evaluated in vitro and in vivo for their potential utility in brain and systemic tumor imaging based upon primarily system A transport with positron emission tomography (PET). METHODS The transport of enantiomers of [(18)F]FAMP 1 and [(18)F]MeFAMP 2 was measured through in vitro uptake assays in human derived cancer cells including A549 (lung), DU145 (prostate), SKOV3 (ovary), MDA MB468 (breast) and U87 (brain) in the presence and absence of amino acid transporter inhibitors. The in vivo biodistribution of these tracers was evaluated using tumor mice xenografts at 15, 30, 60 and 120 min post injection. RESULTS All four tracers showed moderate to high levels of uptake (1-9%ID/5×10(5) cells) by the cancer cell lines tested in vitro. AAT cell inhibition assays demonstrated that (R)-[(18)F]1 and (S)-[(18)F]1 entered these tumor cells via mixed AATs, likely but not limited to system A and system L. In contrast, (R)-[(18)F]2 and (S)-[(18)F]2 showed high selectivity for system A AAT. Similar to the results of in vitro cell studies, the tumor uptake of all four tracers was good to high and persisted over the 2 hours time course of in vivo studies. The accumulation of these tracers was higher in tumor than most normal tissues including blood, brain, muscle, bone, heart, and lung, and the tracers with the highest in vitro selectivity for system A AAT generally demonstrated the best tumor imaging properties. Higher uptake of these tracers was observed in the pancreas, kidney and spleen compared to tumors. CONCLUSIONS These preclinical studies demonstrate good imaging properties in a wide range of tumors for all four amino acids evaluated with (R)-[(18)F]2 having the highest selectivity for system A AAT.
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Affiliation(s)
- Weiping Yu
- Department of Radiology and Imaging Sciences, School of Medicine, Emory University, Atlanta, GA.
| | - Jonathan McConathy
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, GA
| | - Jeffrey J Olson
- Department of Neurosurgery, School of Medicine, Emory University, Atlanta, GA
| | - Mark M Goodman
- Department of Radiology and Imaging Sciences, School of Medicine, Emory University, Atlanta, GA
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89
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Persson P, Fasching A, Teerlink T, Hansell P, Palm F. l
-Citrulline, But Not
l
-Arginine, Prevents Diabetes Mellitus–Induced Glomerular Hyperfiltration and Proteinuria in Rat. Hypertension 2014; 64:323-9. [DOI: 10.1161/hypertensionaha.114.03519] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Diabetes mellitus–induced oxidative stress causes increased renal oxygen consumption and intrarenal tissue hypoxia. Nitric oxide is an important determinant of renal oxygen consumption and electrolyte transport efficiency. The present study investigates whether
l
-arginine or
l
-citrulline to promote nitric oxide production prevents the diabetes mellitus–induced kidney dysfunction. Glomerular filtration rate, renal blood flow, in vivo oxygen consumption, tissue oxygen tension, and proteinuria were investigated in control and streptozotocin-diabetic rats with and without chronic
l
-arginine or
l
-citrulline treatment for 3 weeks. Untreated and
l
-arginine–treated diabetic rats displayed increased glomerular filtration rate (2600±162 versus 1599±127 and 2290±171 versus 1739±138 µL/min per kidney), whereas
l
-citrulline prevented the increase (1227±126 versus 1375±88 µL/min per kidney). Filtration fraction was increased in untreated diabetic rats because of the increase in glomerular filtration rate but not in
l
-arginine– or
l
-citrulline–treated diabetic rats. Urinary protein excretion was increased in untreated and
l
-arginine–treated diabetic rats (142±25 versus 75±7 and 128±7 versus 89±7 µg/min per kidney) but not in diabetic rats administered
l
-citrulline (67±7 versus 61±5 µg/min per kidney). The diabetes mellitus–induced tissue hypoxia, because of elevated oxygen consumption, was unaltered by any of the treatments.
l
-citrulline administered to diabetic rats increases plasma
l
-arginine concentration, which prevents the diabetes mellitus–induced glomerular hyperfiltration, filtration fraction, and proteinuria, possibly by a vascular effect.
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Affiliation(s)
- Patrik Persson
- From the Division of Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden (P.P., A.F., P.H., F.P.); Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands (T.T.); and Division of Drug Research, Department of Medical and Health Sciences (F.P.) and Center for Medical Image Science and Visualization (F.P.), Linköping University, Linköping, Sweden
| | - Angelica Fasching
- From the Division of Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden (P.P., A.F., P.H., F.P.); Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands (T.T.); and Division of Drug Research, Department of Medical and Health Sciences (F.P.) and Center for Medical Image Science and Visualization (F.P.), Linköping University, Linköping, Sweden
| | - Tom Teerlink
- From the Division of Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden (P.P., A.F., P.H., F.P.); Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands (T.T.); and Division of Drug Research, Department of Medical and Health Sciences (F.P.) and Center for Medical Image Science and Visualization (F.P.), Linköping University, Linköping, Sweden
| | - Peter Hansell
- From the Division of Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden (P.P., A.F., P.H., F.P.); Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands (T.T.); and Division of Drug Research, Department of Medical and Health Sciences (F.P.) and Center for Medical Image Science and Visualization (F.P.), Linköping University, Linköping, Sweden
| | - Fredrik Palm
- From the Division of Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden (P.P., A.F., P.H., F.P.); Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands (T.T.); and Division of Drug Research, Department of Medical and Health Sciences (F.P.) and Center for Medical Image Science and Visualization (F.P.), Linköping University, Linköping, Sweden
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90
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Ochiai H, Moriyama J, Kanemaki N, Sato R, Onda K. Analysis of cationic amino acid transport activity in canine lens epithelial cells. Exp Anim 2014; 62:311-7. [PMID: 24172195 PMCID: PMC4160958 DOI: 10.1538/expanim.62.311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Cationic amino acid transport activity in a canine lens epithelial cells (LEC) line was investigated. The transporter activity of arginine was 0.424 ± 0.047 nmol/mg protein min, while the presence of N-ethylmaleimide, an inhibitor of the canine cationic amino acid transporter (CAT), reduced transport activity by 30%. A full-length cDNA sequence of canine CAT1 was 2558 bp long and was predicted to encode the 629 amino acid polypeptides. The deduced amino acid sequence of canine CAT1 showed similarities of 92.1% and 88.6% to those of the human and mouse, respectively. Western blot analysis detected a band at 70 kDa in a membrane protein sample of LEC. RT-PCR analysis confirmed that CAT1 was ubiquitously detected in all tissues examined.
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Affiliation(s)
- Hideharu Ochiai
- Research Institute of Biosciences, Azabu University, School of Veterinary Medicine, 1-17-71 Fuchinobe, Chuou-ku, Sagamihara, Kanagawa 252-5201, Japan
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91
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Shennan DB, Boyd CAR. The functional and molecular entities underlying amino acid and peptide transport by the mammary gland under different physiological and pathological conditions. J Mammary Gland Biol Neoplasia 2014; 19:19-33. [PMID: 24158403 DOI: 10.1007/s10911-013-9305-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 10/15/2013] [Indexed: 12/20/2022] Open
Abstract
This review describes the properties and regulation of the membrane transport proteins which supply the mammary gland with aminonitrogen to support metabolism under different physiological conditions (i.e. pregnancy, lactation and involution). Early studies focussed on characterising amino acid and peptide transport pathways with respect to substrate specificity, kinetics and hormonal regulation to allow a broad picture of the systems within the gland to be established. Recent investigations have concentrated on identifying the individual transporters at the molecular level (i.e. mRNA and protein). Many of the latter studies have identified the molecular correlates of the transport systems uncovered in the earlier functional investigations but in turn have also highlighted the need for more amino acid transport studies to be performed. The transporters function as either cotransporters and exchangers (or both) and act in a coordinated and regulated fashion to support the metabolic needs of the gland. However, it is apparent that a physiological role for a number of the transport proteins has yet to be elucidated. This article highlights the many gaps in our knowledge regarding the precise cellular location of a number of amino acid transporters within the gland. We also describe the role of amino acid transport in mammary cell volume regulation. Finally, the important role that individual mammary transport proteins may have in the growth and proliferation of mammary tumours is discussed.
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Affiliation(s)
- D B Shennan
- Brasenose College, 39 Caerlaverock Road, Prestwick, UK,
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92
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Salsoso R, Guzmán-Gutiérrez E, Arroyo P, Salomón C, Zambrano S, Ruiz-Armenta MV, Blanca AJ, Pardo F, Leiva A, Mate A, Sobrevia L, Vázquez CM. Reduced L-carnitine transport in aortic endothelial cells from spontaneously hypertensive rats. PLoS One 2014; 9:e90339. [PMID: 24587332 PMCID: PMC3938671 DOI: 10.1371/journal.pone.0090339] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 01/30/2014] [Indexed: 12/28/2022] Open
Abstract
Impaired L-carnitine uptake correlates with higher blood pressure in adult men, and L-carnitine restores endothelial function in aortic rings from spontaneously hypertensive rat (SHR). Thus, endothelial dysfunction in hypertension could result from lower L-carnitine transport in this cell type. L-Carnitine transport is mainly mediated by novel organic cation transporters 1 (Octn1, Na+-independent) and 2 (Octn2, Na+-dependent); however, their kinetic properties and potential consequences in hypertension are unknown. We hypothesize that L-carnitine transport kinetic properties will be altered in aortic endothelium from spontaneously hypertensive rats (SHR). L-Carnitine transport was measured at different extracellular pH (pHo 5.5–8.5) in the absence or presence of sodium in rat aortic endothelial cells (RAECs) from non-hypertensive Wistar-Kyoto (WKY) rats and SHR. Octn1 and Octn2 mRNA relative expression was also determined. Dilation of endothelium-intact or denuded aortic rings in response to calcitonine gene related peptide (CGRP, 0.1–100 nmol/L) was measured (myography) in the absence or presence of L-carnitine. Total L-carnitine transport was lower in cells from SHR compared with WKY rats, an effect due to reduced Na+-dependent (Na+dep) compared with Na+-independent (Na+indep) transport components. Saturable L-carnitine transport kinetics show maximal velocity (Vmax), without changes in apparent Km for Na+indep transport in SHR compared with WKY rats. Total and Na+dep component of transport were increased, but Na+indep transport was reduced by extracellular alkalization in WKY rats. However, alkalization reduced total and Na+indep transport in cells from SHR. Octn2 mRNA was higher than Octn-1 mRNA expression in cells from both conditions. Dilation of artery rings in response to CGRP was reduced in vessels from SHR compared with WKY rats. CGRP effect was endothelium-dependent and restored by L-carnitine. All together these results suggest that reduced L-carnitine transport (likely via Na+-dependent Octn2) could limit this compound's potential beneficial effects in RAECs from SHR.
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Affiliation(s)
- Rocío Salsoso
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Enrique Guzmán-Gutiérrez
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo Arroyo
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos Salomón
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sonia Zambrano
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Sevilla, Spain
| | | | - Antonio Jesús Blanca
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Sevilla, Spain
| | - Fabián Pardo
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Andrea Leiva
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alfonso Mate
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Sevilla, Spain
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Herston, Queensland, Australia
- * E-mail: (CMV); (LS)
| | - Carmen María Vázquez
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Sevilla, Spain
- * E-mail: (CMV); (LS)
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93
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Stapelberg M, Zobalova R, Nguyen MN, Walker T, Stantic M, Goodwin J, Pasdar EA, Thai T, Prokopova K, Yan B, Hall S, de Pennington N, Thomas SR, Grant G, Stursa J, Bajzikova M, Meedeniya ACB, Truksa J, Ralph SJ, Ansorge O, Dong LF, Neuzil J. Indoleamine-2,3-dioxygenase elevated in tumor-initiating cells is suppressed by mitocans. Free Radic Biol Med 2014; 67:41-50. [PMID: 24145120 DOI: 10.1016/j.freeradbiomed.2013.10.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2013] [Revised: 10/02/2013] [Accepted: 10/02/2013] [Indexed: 01/07/2023]
Abstract
Tumor-initiating cells (TICs) often survive therapy and give rise to second-line tumors. We tested the plausibility of sphere cultures as models of TICs. Microarray data and microRNA data analysis confirmed the validity of spheres as models of TICs for breast and prostate cancer as well as mesothelioma cell lines. Microarray data analysis revealed the Trp pathway as the only pathway upregulated significantly in all types of studied TICs, with increased levels of indoleamine-2,3-dioxygenase-1 (IDO1), the rate-limiting enzyme of Trp metabolism along the kynurenine pathway. All types of TICs also expressed higher levels of the Trp uptake system consisting of CD98 and LAT1 with functional consequences. IDO1 expression was regulated via both transcriptional and posttranscriptional mechanisms, depending on the cancer type. Serial transplantation of TICs in mice resulted in gradually increased IDO1. Mitocans, represented by α-tocopheryl succinate and mitochondrially targeted vitamin E succinate (MitoVES), suppressed IDO1 in TICs. MitoVES suppressed IDO1 in TICs with functional mitochondrial complex II, involving transcriptional and posttranscriptional mechanisms. IDO1 increase and its suppression by VE analogues were replicated in TICs from primary human glioblastomas. Our work indicates that IDO1 is increased in TICs and that mitocans suppress the protein.
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Affiliation(s)
- Michael Stapelberg
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia.
| | - Renata Zobalova
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia; Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic
| | - Maria Nga Nguyen
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Tom Walker
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia; Department of Neurosurgery, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Marina Stantic
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Jacob Goodwin
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Elham Alizadeh Pasdar
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Thuan Thai
- Centre for Vascular Research, School of Medical Sciences, University of New South Wales, Sydney, 2052 NSW, Australia
| | - Katerina Prokopova
- Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic; Faculty of Science, Charles University, 11000 Prague 1, Czech Republic
| | - Bing Yan
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Susan Hall
- School of Pharmacy, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | | | - Shane R Thomas
- Centre for Vascular Research, School of Medical Sciences, University of New South Wales, Sydney, 2052 NSW, Australia
| | - Gary Grant
- School of Pharmacy, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Jan Stursa
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia; Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague 160 00, Czech Republic
| | - Martina Bajzikova
- Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic
| | - Adrian C B Meedeniya
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Jaroslav Truksa
- Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic
| | - Stephen J Ralph
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Olaf Ansorge
- Department of Neurosurgery, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Lan-Feng Dong
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia
| | - Jiri Neuzil
- School of Medical Science, Griffith Health Institute, Griffith University, Southport, 4222 QLD, Australia; Institute of Biotechnology, Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic.
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94
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Yang J, Tan Q, Zhu W, Chen C, Liang X, Pan L. Cloning and molecular characterization of cationic amino acid transporter y⁺LAT1 in grass carp (Ctenopharyngodon idellus). FISH PHYSIOLOGY AND BIOCHEMISTRY 2014; 40:93-104. [PMID: 23817987 DOI: 10.1007/s10695-013-9827-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 06/18/2013] [Indexed: 06/02/2023]
Abstract
The solute carrier family 7A, member 7 gene encodes the light chain- y⁺L amino acid transporter-1 (y⁺LAT1) of the heterodimeric carrier responsible for cationic amino acid (CAA) transport across the basolateral membranes of epithelial cells in intestine and kidney. Rising attention has been given to y⁺LAT1 involved in CAA metabolic pathways and growth control. The molecular characterization and function analysis of y⁺LAT1 in grass carp (Ctenopharyngodon idellus) is currently unknown. In the present study, full-length cDNA (2,688 bp), which encodes y⁺LAT1 and contains a 5'-untranslated region (319 bp), an open reading frame (1,506 bp) and a 3'-untranslated region (863 bp), has been cloned from grass carp. Amino acid sequence of grass carp y⁺LAT1 contains 11 transmembrane domains and shows 95 %, 80 % and 75 % sequence similarity to zebra fish, amphibian and mammalian y⁺LAT1, respectively. The tissue distribution and expression regulation by fasting of y⁺LAT1 mRNA were analyzed using real-time PCR. Our results showed that y⁺LAT1 mRNA was highly expressed in midgut, foregut and spleen while weakly expressed in hindgut, kidney, gill, brain, heart, liver and muscle. Nutritional status significantly influenced y⁺LAT1 mRNA expression in fish tissues, such as down-regulation of y⁺LAT1 mRNA expression after fasting (14 days).
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Affiliation(s)
- Jixuan Yang
- Fisheries College, Huazhong Agricultural University, Wuhan, 430070, China
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95
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Guzmán-Gutiérrez E, Arroyo P, Salsoso R, Fuenzalida B, Sáez T, Leiva A, Pardo F, Sobrevia L. Role of Insulin and Adenosine in the Human Placenta Microvascular and Macrovascular Endothelial Cell Dysfunction in Gestational Diabetes Mellitus. Microcirculation 2014; 21:26-37. [DOI: 10.1111/micc.12077] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 07/18/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Enrique Guzmán-Gutiérrez
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Pablo Arroyo
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Rocío Salsoso
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Bárbara Fuenzalida
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
- Biomedical Department; Faculty of Health Sciences; Universidad de Antofagasta; Antofagasta Chile
| | - Tamara Sáez
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Andrea Leiva
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Fabián Pardo
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
- University of Queensland Centre for Clinical Research; Herston Queensland Australia
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96
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Lorin J, Zeller M, Guilland JC, Cottin Y, Vergely C, Rochette L. Arginine and nitric oxide synthase: regulatory mechanisms and cardiovascular aspects. Mol Nutr Food Res 2014; 58:101-16. [PMID: 23740826 DOI: 10.1002/mnfr.201300033] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 03/04/2013] [Accepted: 03/06/2013] [Indexed: 12/17/2022]
Abstract
L-Arginine (L-Arg) is a conditionally essential amino acid in the human diet. The most common dietary sources of L-Arg are meat, poultry and fish. L-Arg is the precursor for the synthesis of nitric oxide (NO); a key signaling molecule via NO synthase (NOS). Endogenous NOS inhibitors such as asymmetric-dimethyl-L-Arg inhibit NO synthesis in vivo by competing with L-Arg at the active site of NOS. In addition, NOS possesses the ability to be "uncoupled" to produce superoxide anion instead of NO. Reduced NO bioavailability may play an essential role in cardiovascular pathologies and metabolic diseases. L-Arg deficiency syndromes in humans involve endothelial inflammation and immune dysfunctions. Exogenous administration of L-Arg restores NO bioavailability, but it has not been possible to demonstrate, that L-Arg supplementation improved endothelial function in cardiovascular disease such as heart failure or hypertension. L-Arg supplementation may be a novel therapy for obesity and metabolic syndrome. The utility of l-Arg supplementation in the treatment of L-Arg deficiency syndromes remains to be established. Clinical trials need to continue to determine the optimal concentrations and combinations of L-Arg, with other protective compounds such as tetrahydrobiopterin (BH4 ), and antioxidants to combat oxidative stress that drives down NO production in humans.
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Affiliation(s)
- Julie Lorin
- Laboratoire de Physiopathologie et Pharmacologies Cardio-Métaboliques (LPPCM), Inserm UMR866, Facultés de Médecine et de Pharmacie, Université de Bourgogne, Dijon, France
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97
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Su Y. Regulation of endothelial nitric oxide synthase activity by protein-protein interaction. Curr Pharm Des 2014; 20:3514-20. [PMID: 24180383 PMCID: PMC7039309 DOI: 10.2174/13816128113196660752] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/21/2013] [Indexed: 02/07/2023]
Abstract
Endothelial nitric oxide synthase (eNOS) is expressed in vascular endothelial cells and plays an important role in the regulation of vascular tone, platelet aggregation and angiogenesis. Protein-protein interactions represent an important posttranslational mechanism for eNOS regulation. eNOS has been shown to interact with a variety of regulatory and structural proteins which provide fine tuneup of eNOS activity and eNOS protein trafficking between plasma membrane and intracellular membranes in a number of physiological and pathophysiological processes. eNOS interacts with calmodulin, heat shock protein 90 (Hsp90), dynamin-2, β-actin, tubulin, porin, high-density lipoprotein (HDL) and apolipoprotein AI (ApoAI), resulting in increases in eNOS activity. The negative eNOS interacting proteins include caveolin, G protein-coupled receptors (GPCR), nitric oxide synthase-interacting protein (NOSIP), and nitric oxide synthase trafficking inducer (NOSTRIN). Dynamin-2, NOSIP, NOSTRIN, and cytoskeleton are also involved in eNOS trafficking in endothelial cells. In addition, eNOS associations with cationic amino acid transporter-1 (CAT-1), argininosuccinate synthase (ASS), argininosuccinate lyase (ASL), and soluble guanylate cyclase (sGC) facilitate directed delivery of substrate (L-arginine) to eNOS and optimizing NO production and NO action on its target. Regulation of eNOS by protein-protein interactions would provide potential targets for pharmacological interventions in NO-compromised cardiovascular diseases.
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Affiliation(s)
- Yunchao Su
- Department of Pharmacology and Toxicology, Medical College of Georgia, Georgia Regents University, 1120 15th Street, Augusta, GA 30912.
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98
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Müller A, Chiotellis A, Keller C, Ametamey SM, Schibli R, Mu L, Krämer SD. Imaging Tumour ATB0,+ Transport Activity by PET with the Cationic Amino Acid O-2((2-[18F]fluoroethyl)methyl-amino)ethyltyrosine. Mol Imaging Biol 2013; 16:412-20. [DOI: 10.1007/s11307-013-0711-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 11/03/2013] [Accepted: 11/22/2013] [Indexed: 11/28/2022]
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99
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Daima HK, Selvakannan PR, Shukla R, Bhargava SK, Bansal V. Fine-tuning the antimicrobial profile of biocompatible gold nanoparticles by sequential surface functionalization using polyoxometalates and lysine. PLoS One 2013; 8:e79676. [PMID: 24147146 PMCID: PMC3798406 DOI: 10.1371/journal.pone.0079676] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 10/04/2013] [Indexed: 02/07/2023] Open
Abstract
Antimicrobial action of nanomaterials is typically assigned to the nanomaterial composition, size and/or shape, whereas influence of complex corona stabilizing the nanoparticle surface is often neglected. We demonstrate sequential surface functionalization of tyrosine-reduced gold nanoparticles (AuNPs(Tyr)) with polyoxometalates (POMs) and lysine to explore controlled chemical functionality-driven antimicrobial activity. Our investigations reveal that highly biocompatible gold nanoparticles can be tuned to be a strong antibacterial agent by fine-tuning their surface properties in a controllable manner. The observation from the antimicrobial studies on a gram negative bacterium Escherichia coli were further validated by investigating the anticancer properties of these step-wise surface-controlled materials against A549 human lung carcinoma cells, which showed a similar toxicity pattern. These studies highlight that the nanomaterial toxicity and biological applicability are strongly governed by their surface corona.
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Affiliation(s)
- Hemant K. Daima
- NanoBiotechnology Research Laboratory, School of Applied Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - P. R. Selvakannan
- NanoBiotechnology Research Laboratory, School of Applied Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - Ravi Shukla
- NanoBiotechnology Research Laboratory, School of Applied Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - Suresh K. Bhargava
- NanoBiotechnology Research Laboratory, School of Applied Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
| | - Vipul Bansal
- NanoBiotechnology Research Laboratory, School of Applied Sciences, Royal Melbourne Institute of Technology University, Melbourne, Victoria, Australia
- * E-mail:
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100
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The SLC3 and SLC7 families of amino acid transporters. Mol Aspects Med 2013; 34:139-58. [PMID: 23506863 DOI: 10.1016/j.mam.2012.10.007] [Citation(s) in RCA: 467] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 08/15/2012] [Indexed: 01/18/2023]
Abstract
Amino acids are necessary for all living cells and organisms. Specialized transporters mediate the transfer of amino acids across plasma membranes. Malfunction of these proteins can affect whole-body homoeostasis giving raise to diverse human diseases. Here, we review the main features of the SLC3 and SLC7 families of amino acid transporters. The SLC7 family is divided into two subfamilies, the cationic amino acid transporters (CATs), and the L-type amino acid transporters (LATs). The latter are the light or catalytic subunits of the heteromeric amino acid transporters (HATs), which are associated by a disulfide bridge with the heavy subunits 4F2hc or rBAT. These two subunits are glycoproteins and form the SLC3 family. Most CAT subfamily members were functionally characterized and shown to function as facilitated diffusers mediating the entry and efflux of cationic amino acids. In certain cells, CATs play an important role in the delivery of L-arginine for the synthesis of nitric oxide. HATs are mostly exchangers with a broad spectrum of substrates and are crucial in renal and intestinal re-absorption and cell redox balance. Furthermore, the role of the HAT 4F2hc/LAT1 in tumor growth and the application of LAT1 inhibitors and PET tracers for reduction of tumor progression and imaging of tumors are discussed. Finally, we describe the link between specific mutations in HATs and the primary inherited aminoacidurias, cystinuria and lysinuric protein intolerance.
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