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Xiang J, Keep RF. Proton-Coupled Oligopeptide Transport (Slc15) in the Brain: Past and Future Research. Pharm Res 2023; 40:2533-2540. [PMID: 37308743 DOI: 10.1007/s11095-023-03550-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 06/06/2023] [Indexed: 06/14/2023]
Abstract
This mini-review describes the role of the solute carrier (SLC)15 family of proton-coupled oligopeptide transporters (POTs) and particularly Pept2 (Slc15A2) and PhT1 (Slc15A4) in the brain. That family transports endogenous di- and tripeptides and peptidomimetics but also a number of drugs. The review focuses on the pioneering work of David E. Smith in the field in identifying the impact of PepT2 at the choroid plexus (the blood-CSF barrier) as well as PepT2 and PhT1 in brain parenchymal cells. It also discusses recent findings and future directions in relation to brain POTs including cellular and subcellular localization, regulatory pathways, transporter structure, species differences and disease states.
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Affiliation(s)
- Jianming Xiang
- Department of Neurosurgery, University of Michigan, R5018 BSRB 109 Zina Pitcher Place, Ann Arbor, MI, 48109, USA
| | - Richard F Keep
- Department of Neurosurgery, University of Michigan, R5018 BSRB 109 Zina Pitcher Place, Ann Arbor, MI, 48109, USA.
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2
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Custódio TF, Killer M, Yu D, Puente V, Teufel DP, Pautsch A, Schnapp G, Grundl M, Kosinski J, Löw C. Molecular basis of TASL recruitment by the peptide/histidine transporter 1, PHT1. Nat Commun 2023; 14:5696. [PMID: 37709742 PMCID: PMC10502012 DOI: 10.1038/s41467-023-41420-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 09/04/2023] [Indexed: 09/16/2023] Open
Abstract
PHT1 is a histidine /oligopeptide transporter with an essential role in Toll-like receptor innate immune responses. It can act as a receptor by recruiting the adaptor protein TASL which leads to type I interferon production via IRF5. Persistent stimulation of this signalling pathway is known to be involved in the pathogenesis of systemic lupus erythematosus (SLE). Understanding how PHT1 recruits TASL at the molecular level, is therefore clinically important for the development of therapeutics against SLE and other autoimmune diseases. Here we present the Cryo-EM structure of PHT1 stabilized in the outward-open conformation. By combining biochemical and structural modeling techniques we propose a model of the PHT1-TASL complex, in which the first 16 N-terminal TASL residues fold into a helical structure that bind in the central cavity of the inward-open conformation of PHT1. This work provides critical insights into the molecular basis of PHT1/TASL mediated type I interferon production.
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Affiliation(s)
- Tânia F Custódio
- Centre for Structural Systems Biology (CSSB), Notkestraße 85, 22607, Hamburg, Germany
- European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607, Hamburg, Germany
| | - Maxime Killer
- Centre for Structural Systems Biology (CSSB), Notkestraße 85, 22607, Hamburg, Germany
- European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607, Hamburg, Germany
- Collaboration for joint PhD degree between EMBL, and Heidelberg University, Faculty of Biosciences, 69120, Heidelberg, Germany
| | - Dingquan Yu
- Centre for Structural Systems Biology (CSSB), Notkestraße 85, 22607, Hamburg, Germany
- European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607, Hamburg, Germany
- Collaboration for joint PhD degree between EMBL, and Heidelberg University, Faculty of Biosciences, 69120, Heidelberg, Germany
| | - Virginia Puente
- Centre for Structural Systems Biology (CSSB), Notkestraße 85, 22607, Hamburg, Germany
- European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607, Hamburg, Germany
| | - Daniel P Teufel
- Boehringer Ingelheim Pharma, Birkendorferstraße 65, 88397, Biberach, Germany
| | - Alexander Pautsch
- Boehringer Ingelheim Pharma, Birkendorferstraße 65, 88397, Biberach, Germany
| | - Gisela Schnapp
- Boehringer Ingelheim Pharma, Birkendorferstraße 65, 88397, Biberach, Germany
| | - Marc Grundl
- Boehringer Ingelheim Pharma, Birkendorferstraße 65, 88397, Biberach, Germany
| | - Jan Kosinski
- Centre for Structural Systems Biology (CSSB), Notkestraße 85, 22607, Hamburg, Germany
- European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607, Hamburg, Germany
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117, Heidelberg, Germany
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), Notkestraße 85, 22607, Hamburg, Germany.
- European Molecular Biology Laboratory (EMBL) Hamburg, Notkestraße 85, 22607, Hamburg, Germany.
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3
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Zhang H, Bernaleau L, Delacrétaz M, Hasanovic E, Drobek A, Eibel H, Rebsamen M. SLC15A4 controls endolysosomal TLR7-9 responses by recruiting the innate immune adaptor TASL. Cell Rep 2023; 42:112916. [PMID: 37527038 DOI: 10.1016/j.celrep.2023.112916] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 06/16/2023] [Accepted: 07/17/2023] [Indexed: 08/03/2023] Open
Abstract
Endolysosomal Toll-like receptors (TLRs) play crucial roles in immune responses to pathogens, while aberrant activation of these pathways is associated with autoimmune diseases, including systemic lupus erythematosus (SLE). The endolysosomal solute carrier family 15 member 4 (SLC15A4) is required for TLR7/8/9-induced responses and disease development in SLE models. SLC15A4 has been proposed to affect TLR7-9 activation through its transport activity, as well as by assembling an IRF5-activating complex with TASL, but the relative contribution of these functions remains unclear. Here, we show that the essential role of SLC15A4 is to recruit TASL to endolysosomes, while its transport activity is dispensable when TASL is tethered to this compartment. Endolysosomal-localized TASL rescues TLR7-9-induced IRF5 activation as well as interferon β and cytokine production in SLC15A4-deficient cells. SLC15A4 acts as signaling scaffold, and this function is essential to control TLR7-9-mediated inflammatory responses. These findings support targeting the SLC15A4-TASL complex as a potential therapeutic strategy for SLE and related diseases.
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Affiliation(s)
- Haobo Zhang
- Department of Immunobiology, University of Lausanne, Ch. des Boveresses 155, 1066 Epalinges, Switzerland
| | - Léa Bernaleau
- Department of Immunobiology, University of Lausanne, Ch. des Boveresses 155, 1066 Epalinges, Switzerland
| | - Maeva Delacrétaz
- Department of Immunobiology, University of Lausanne, Ch. des Boveresses 155, 1066 Epalinges, Switzerland
| | - Ed Hasanovic
- Department of Immunobiology, University of Lausanne, Ch. des Boveresses 155, 1066 Epalinges, Switzerland
| | - Ales Drobek
- Department of Immunobiology, University of Lausanne, Ch. des Boveresses 155, 1066 Epalinges, Switzerland
| | - Hermann Eibel
- Department of Rheumatology and Clinical Immunology, Medical Center and Faculty of Medicine, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany; Center for Chronic Immunodeficiency, Medical Center and Faculty of Medicine, University of Freiburg, Breisacherstr. 115, 79106 Freiburg, Germany
| | - Manuele Rebsamen
- Department of Immunobiology, University of Lausanne, Ch. des Boveresses 155, 1066 Epalinges, Switzerland.
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Bioactive and Sensory Di- and Tripeptides Generated during Dry-Curing of Pork Meat. Int J Mol Sci 2023; 24:ijms24021574. [PMID: 36675084 PMCID: PMC9866438 DOI: 10.3390/ijms24021574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
Dry-cured pork products, such as dry-cured ham, undergo an extensive proteolysis during manufacturing process which determines the organoleptic properties of the final product. As a result of endogenous pork muscle endo- and exopeptidases, many medium- and short-chain peptides are released from muscle proteins. Many of them have been isolated, identified, and characterized, and some peptides have been reported to exert relevant bioactivity with potential benefit for human health. However, little attention has been given to di- and tripeptides, which are far less known, although they have received increasing attention in recent years due to their high potential relevance in terms of bioactivity and role in taste development. This review gathers the current knowledge about di- and tripeptides, regarding their bioactivity and sensory properties and focusing on their generation during long-term processing such as dry-cured pork meats.
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Yang H, Wang Z, Shi S, Yu Q, Liu M, Zhang Z. Identification of cerebrospinal fluid metabolites as biomarkers for neurobrucellosis by liquid chromatography-mass spectrometry approach. Bioengineered 2022; 13:6996-7010. [PMID: 35249459 PMCID: PMC8974019 DOI: 10.1080/21655979.2022.2037954] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Neurobrucellosis is the most morbid form in brucellosis disease. Metabolomics is an emerging method which intends to explore the global alterations of various metabolites in samples. We aimed to identify metabolites in cerebrospinal fluid (CSF) as biomarkers that were potentially unique for neurobrucellosis. CSF samples from 25 neurobrucellosis patients and 25 normal controls (uninfected patients with hydrocephalus) were collected for metabolite detection using liquid chromatography-mass spectrometry (LC-MS) approach. Inflammatory cytokines in CSF were measured with Enzyme-linked immunosorbent assay (ELISA). The base peak chromatogram in CSF samples showed that small-molecule metabolites were well separated. Principal Component Analysis (PCA) analysis exhibited the examined samples were arranged in two main clusters in accordance with their group. Projection to Latent Structures Discriminant Analysis (PLS-DA) revealed there was a noticeable separation between neurobrucellosis and normal groups. Orthogonal Partial Least-Squares-Discriminant Analysis (OPLS-DA) could responsibly illuminate the differences between neurobrucellosis and normal controls. Neurobrucellosis showed a total of 155 differentiated metabolites. Prominent potential biomarkers including 30 metabolites were then selected out, regarded as more capable of distinguishing neurobrucellosis. TNF-α and IL-6 in CSF were remarkably increased in neurobrucellosis. We presented the heatmaps and correlation analyses among the identified 30 potential biomarkers. In conclusion, this study showed that CSF metabolomics based on LC-MS could distinguish neurobrucellosis patients from normal controls. Our data offered perspectives for diagnosis and treatment for neurobrucellosis.
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Affiliation(s)
- Hao Yang
- Department of Radiation Oncology, Inner Mongolia Cancer Hospital & Affiliated People's Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Zhenfei Wang
- Department of Radiation Oncology, Inner Mongolia Cancer Hospital & Affiliated People's Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Shujun Shi
- Department of Neurology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Qin Yu
- Department of Radiation Oncology, Inner Mongolia Cancer Hospital & Affiliated People's Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Meiling Liu
- Department of Neurology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
| | - Zhelin Zhang
- Department of Neurology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China
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Khatami M. Deceptology in cancer and vaccine sciences: Seeds of immune destruction-mini electric shocks in mitochondria: Neuroplasticity-electrobiology of response profiles and increased induced diseases in four generations - A hypothesis. Clin Transl Med 2020; 10:e215. [PMID: 33377661 PMCID: PMC7749544 DOI: 10.1002/ctm2.215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/08/2020] [Accepted: 10/13/2020] [Indexed: 12/16/2022] Open
Abstract
From Rockefeller's support of patent medicine to Gates' patent vaccines, medical establishment invested a great deal in intellectual ignorance. Through the control over medical education and research it has created a public illusion to prop up corporate profit and encouraged the lust for money and power. An overview of data on cancer and vaccine sciences, the status of Americans' health, a survey of repeated failed projects, economic toxicity, and heavy drug consumption or addiction among young and old provide compelling evidence that in the twentieth century nearly all classic disease categories (congenital, inheritance, neonatal, or induced) shifted to increase induced diseases. Examples of this deceptology in ignoring or minimizing, and mocking fundamental discoveries and theories in cancer and vaccine sciences are attacks on research showing that (a), effective immunity is responsible for defending and killing pathogens and defective cancerous cells, correcting and repairing genetic mutations; (b) viruses cause cancer; and (c), abnormal gene mutations are often the consequences of (and secondary to) disturbances in effective immunity. The outcomes of cancer reductionist approaches to therapies reveal failure rates of 90% (+/-5) for solid tumors; loss of over 50 million lives and waste of $30-50 trillions on too many worthless, out-of-focus, and irresponsible projects. Current emphasis on vaccination of public with pathogen-specific vaccines and ingredients seems new terms for drugging young and old. Cumulative exposures to low level carcinogens and environmental hazards or high energy electronic devices (EMF; 5G) are additional triggers to vaccine toxicities (antigen-mitochondrial overload) or "seeds of immune destruction" that create mini electrical shocks (molecular sinks holes) in highly synchronized and regulated immune network that retard time-energy-dependent biorhythms in organs resulting in causes, exacerbations or consequences of mild, moderate or severe immune disorders. Four generations of drug-dependent Americans strongly suggest that medical establishment has practiced decades of intellectual deception through its claims on "war on cancer"; that cancer is 100, 200, or 1000 diseases; identification of "individual" genetic mutations to cure diseases; "vaccines are safe". Such immoral and unethical practices, along with intellectual harassment and bullying, censoring or silencing of independent and competent professionals ("Intellectual Me Too") present grave concerns, far greater compared with the sexual harassment of 'Me Too' movement that was recently spearheaded by NIH. The principal driving forces behind conducting deceptive and illogical medical/cancer and vaccine projects seem to be; (a) huge return of investment and corporate profit for selling drugs and vaccines; (b) maintenance of abusive power over public health; (c) global control of population growth via increased induction of diseases, infertility, decline in life-span, and death. An overview of accidental discoveries that we established and extended since 1980s, on models of acute and chronic ocular inflammatory diseases, provides series of the first evidence for a direct link between inflammation and multistep immune dysfunction in tumorigenesis and angiogenesis. Results are relevant to demonstrate that current emphasis on vaccinating the unborn, newborn, or infant would induce immediate or long-term immune disorders (eg, low birth weight, preterm birth, fatigue, autism, epilepsy/seizures, BBB leakage, autoimmune, neurodegenerative or digestive diseases, obesity, diabetes, cardiovascular problems, or cancers). Vaccination of the unborn is likely to disturb trophoblast-embryo-fetus-placenta biology and orderly growth of embryo-fetus, alter epithelial-mesenchymal transition or constituent-inducible receptors, damage mitochondria, and diverse function of histamine-histidine pathways. Significant increased in childhood illnesses are likely due to toxicities of vaccine and incipient (eg, metals [Al, Hg], detergents, fetal tissue, DNA/RNA) that retard bioenergetics of mitochondria, alter polarization-depolarization balance of tumoricidal (Yin) and tumorigenic (Yang) properties of immunity. Captivated by complex electobiology of immunity, this multidisciplinary perspective is an attempt to initiate identifying bases for increased induction of immune disorders in three to four generations in America. We hypothesize that (a) gene-environment-immune biorhythms parallel neuronal function (brain neuroplasticity) with super-packages of inducible (adaptive or horizontal) electronic signals and (b) autonomic sympathetic and parasympathetic circuitry that shape immunity (Yin-Yang) cannot be explained by limited genomics (innate, perpendicular) that conventionally explain certain inherited diseases (eg, sickle cell anemia, progeria). Future studies should focus on deep learning of complex electrobiology of immunity that requires differential bioenergetics from mitochondria and cytoplasm. Approaches to limit or control excessive activation of gene-environment-immunity are keys to assess accurate disease risk formulations, prevent inducible diseases, and develop universal safe vaccines that promote health, the most basic human right.
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Affiliation(s)
- Mahin Khatami
- Inflammation, Aging and Cancer, National Cancer Institute (NCI)the National Institutes of Health (NIH) (Retired)BethesdaMarylandUSA
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Viennois E, Pujada A, Zen J, Merlin D. Function, Regulation, and Pathophysiological Relevance of the POT Superfamily, Specifically PepT1 in Inflammatory Bowel Disease. Compr Physiol 2018; 8:731-760. [PMID: 29687900 DOI: 10.1002/cphy.c170032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mammalian members of the proton-coupled oligopeptide transporter family are integral membrane proteins that mediate the cellular uptake of di/tripeptides and peptide-like drugs and couple substrate translocation to the movement of H+ , with the transmembrane electrochemical proton gradient providing the driving force. Peptide transporters are responsible for the (re)absorption of dietary and/or bacterial di- and tripeptides in the intestine and kidney and maintaining homeostasis of neuropeptides in the brain. These proteins additionally contribute to absorption of a number of pharmacologically important compounds. In this overview article, we have provided updated information on the structure, function, expression, localization, and activities of PepT1 (SLC15A1), PepT2 (SLC15A2), PhT1 (SLC15A4), and PhT2 (SLC15A3). Peptide transporters, in particular, PepT1 are discussed as drug-delivery systems in addition to their implications in health and disease. Particular emphasis has been placed on the involvement of PepT1 in the physiopathology of the gastrointestinal tract, specifically, its role in inflammatory bowel diseases. © 2018 American Physiological Society. Compr Physiol 8:731-760, 2018.
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Affiliation(s)
- Emilie Viennois
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Adani Pujada
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Jane Zen
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Didier Merlin
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA.,Veterans Affairs Medical Center, Decatur, Georgia, USA
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Wang XX, Li YB, Feng MR, Smith DE. Semi-Mechanistic Population Pharmacokinetic Modeling of L-Histidine Disposition and Brain Uptake in Wildtype and Pht1 Null Mice. Pharm Res 2018; 35:19. [PMID: 29305823 DOI: 10.1007/s11095-017-2322-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 11/22/2017] [Indexed: 01/06/2023]
Abstract
PURPOSE To develop a semi-mechanistic population pharmacokinetic (PK) model to quantitate the disposition kinetics of L-histidine, a peptide-histidine transporter 1 (PHT1) substrate, in the plasma, cerebrospinal fluid and brain parenchyma of wildtype (WT) and Pht1 knockout (KO) mice. METHODS L-[14C]Hisidine (L-His) was administrated to WT and KO mice via tail vein injection, after which plasma, cerebrospinal fluid (CSF) and brain parenchyma samples were collected. A PK model was developed using non-linear mixed effects modeling (NONMEM). The disposition of L-His between the plasma, brain, and CSF was described by a combination of PHT1-mediated uptake, CSF bulk flow and first-order micro-rate constants. RESULTS The PK profile of L-His was best described by a four-compartment model. A more rapid uptake of L-His in brain parenchyma was observed in WT mice due to PHT1-mediated uptake, a process characterized by a Michaelis-Menten component (Vmax = 0.051 nmoL/min and Km = 34.94 μM). CONCLUSIONS A semi-mechanistic population PK model was successfully developed, for the first time, to quantitatively characterize the disposition kinetics of L-His in brain under in vivo conditions. This model may prove a useful tool in predicting the uptake of L-His, and possibly other PHT1 peptide/mimetic substrates, for drug delivery to the brain.
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Affiliation(s)
- Xiao-Xing Wang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church Street, Ann Arbor, Michigan, 48109-1065, USA
| | - Yang-Bing Li
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Meihua R Feng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church Street, Ann Arbor, Michigan, 48109-1065, USA
| | - David E Smith
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, 428 Church Street, Ann Arbor, Michigan, 48109-1065, USA.
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Song F, Hu Y, Wang Y, Smith DE, Jiang H. Functional Characterization of Human Peptide/Histidine Transporter 1 in Stably Transfected MDCK Cells. Mol Pharm 2018; 15:385-393. [PMID: 29224352 DOI: 10.1021/acs.molpharmaceut.7b00728] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The proton-coupled oligopeptide transporter PHT1 (SLC15A4), which facilitates cross-membrane transport of histidine and small peptides from inside the endosomes or lysosomes to cytosol, plays an important role in intracellular peptides homeostasis and innate immune responses. However, it remains a challenge to elucidate functional properties of the PHT1 transporter because of its subcellular localization. The purpose of this study was to resort hPHT1 protein from the subcellular to outer cell membrane of MDCK cells stably transfected with human PHT1 mutants, and to characterize its functional activity in these cells. Using this model, the functional activity of hPHT1 was evaluated by cellular uptake studies with d3-l-histidine, GlySar, and the bacterial peptidoglycan products MDP and Tri-DAP. We found that the disruption of two dileucine motifs was indispensable for hPHT1 transporter being preferentially targeting to plasma membranes. hPHT1 showed high affinity for d3-l-histidine and low affinity for GlySar, with Km values of 16.3 ± 1.9 μM and 1.60 ± 0.30 mM, respectively. Moreover, the bacterial peptidoglycan components MDP and Tri-DAP were shown conclusively to be hPHT1 substrates. The uptake of MDP by hPHT1 was inhibited by di/tripeptides and peptide-like drugs, but not by glycine and acyclovir. The functional activity of hPHT1 was also pH-dependent, with an optimal cellular uptake in buffer pH 6.5. Taken together, we established a novel cell model to evaluate the function of hPHT1 in vitro, and confirmed that MDP and Tri-DAP were substrates of hPHT1. Our findings suggest that PHT1 may serve as a potential target for reducing the immune responses and for drug treatment of inflammatory diseases.
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Affiliation(s)
- Feifeng Song
- Laboratory of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences, Zhejiang University , Zhejiang 310058, China
| | - Yongjun Hu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Yuqing Wang
- Laboratory of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences, Zhejiang University , Zhejiang 310058, China
| | - David E Smith
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan , Ann Arbor, Michigan 48109, United States
| | - Huidi Jiang
- Laboratory of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences, Zhejiang University , Zhejiang 310058, China
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Simm F, Griesbeck A, Choukair D, Weiß B, Paramasivam N, Klammt J, Schlesner M, Wiemann S, Martinez C, Hoffmann GF, Pfäffle RW, Bettendorf M, Rappold GA. Identification of SLC20A1 and SLC15A4 among other genes as potential risk factors for combined pituitary hormone deficiency. Genet Med 2017; 20:728-736. [DOI: 10.1038/gim.2017.165] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 08/14/2017] [Indexed: 12/25/2022] Open
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