1
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Jian L, Zhang Q, Yao D, Wang Q, Chen M, Xia Y, Li S, Shen Y, Cao M, Qin A, Li L, Cao Y. The structural insight into the functional modulation of human anion exchanger 3. Nat Commun 2024; 15:6134. [PMID: 39033175 PMCID: PMC11271275 DOI: 10.1038/s41467-024-50572-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 07/15/2024] [Indexed: 07/23/2024] Open
Abstract
Anion exchanger 3 (AE3) is pivotal in regulating intracellular pH across excitable tissues, yet its structural intricacies and functional dynamics remain underexplored compared to other anion exchangers. This study unveils the structural insights into human AE3, including the cryo-electron microscopy structures for AE3 transmembrane domains (TMD) and a chimera combining AE3 N-terminal domain (NTD) with AE2 TMD (hAE3NTD2TMD). Our analyzes reveal a substrate binding site, an NTD-TMD interlock mechanism, and a preference for an outward-facing conformation. Unlike AE2, which has more robust acid-loading capabilities, AE3's structure, including a less stable inward-facing conformation due to missing key NTD-TMD interactions, contributes to its moderated pH-modulating activity and increased sensitivity to the inhibitor DIDS. These structural differences underline AE3's distinct functional roles in specific tissues and underscore the complex interplay between structural dynamics and functional specificity within the anion exchanger family, enhancing our understanding of the physiological and pathological roles of the anion exchanger family.
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Affiliation(s)
- Liyan Jian
- Department of Orthopaedics, Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
| | - Qing Zhang
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, USA
| | - Deqiang Yao
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
- Institute of Aging & Tissue Regeneration, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qian Wang
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
| | - Moxin Chen
- Department of Ophthalmology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Ying Xia
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
| | - Shaobai Li
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
| | - Yafeng Shen
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
| | - Mi Cao
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China
| | - An Qin
- Department of Orthopaedics, Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
- Department of Orthopaedics, Shanghai Frontiers Science Center of Degeneration and Regeneration in Skeletal System, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Lin Li
- Department of Ophthalmology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China.
| | - Yu Cao
- Department of Orthopaedics, Shanghai Key Laboratory of Orthopaedic Implant, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, China.
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2
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Mungara P, Waiss M, Hartwig S, Burger D, Cordat E. Unraveling the molecular landscape of kAE1: a narrative review. Can J Physiol Pharmacol 2024; 102:396-407. [PMID: 38669699 DOI: 10.1139/cjpp-2023-0482] [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] [Indexed: 04/28/2024]
Abstract
Kidney anion exchanger 1 (kAE1) is an isoform of the AE1 protein encoded by the SLC4A1 gene. It is a basolateral membrane protein expressed by α-intercalated cells in the connecting tubules and collecting duct of the kidney. Its main function is to exchange bicarbonate and chloride ions between the blood and urine to maintain blood pH at physiological threshold. The kAE1 protein undergoes multiple post-translational modifications such as phosphorylation and ubiquitination and interacts with many different proteins such as claudin-4 and carbonic anhydrase II. Mutations in the gene may lead to the development of distal renal tubular acidosis, characterized by the failure to acidify the urine, which may result in nephrocalcinosis and in more severe cases, renal failure. In this review, we discuss the structure and function of kAE1, its post-translational modifications, and protein-protein interactions. Finally, we discuss insights gained from the study of kAE1 mutations in humans and in mice.
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Affiliation(s)
- Priyanka Mungara
- Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine, College of Health Sciences, University of Alberta, Edmonton, AB, Canada
| | - Moubarak Waiss
- School of Pharmaceutical Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Sunny Hartwig
- Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| | - Dylan Burger
- School of Pharmaceutical Sciences, University of Ottawa, Ottawa, ON, Canada
- Ottawa Hospital Research Institute, Kidney Research Centre, Ottawa, ON, Canada
| | - Emmanuelle Cordat
- Department of Physiology, Membrane Protein Disease Research Group, Faculty of Medicine, College of Health Sciences, University of Alberta, Edmonton, AB, Canada
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3
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Vitzthum H, Meyer-Schwesinger C, Ehmke H. Novel functions of the anion exchanger AE4 (SLC4A9). Pflugers Arch 2024; 476:555-564. [PMID: 38195948 PMCID: PMC11006790 DOI: 10.1007/s00424-023-02899-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/12/2023] [Accepted: 12/14/2023] [Indexed: 01/11/2024]
Abstract
The kidney plays a crucial role in acid-base homeostasis. In the distal nephron, α-intercalated cells contribute to urinary acid (H+) secretion and β-intercalated cells accomplish urinary base (HCO3-) secretion. β-intercalated cells regulate the acid base status through modulation of the apical Cl-/HCO3- exchanger pendrin (SLC26A4) activity. In this review, we summarize and discuss our current knowledge of the physiological role of the renal transporter AE4 (SLC4A9). The AE4, as cation-dependent Cl-/HCO3- exchanger, is exclusively expressed in the basolateral membrane of β-intercalated cells and is essential for the sensing of metabolic acid-base disturbances in mice, but not for renal sodium reabsorption and plasma volume control. Potential intracellular signaling pathways are discussed that might link basolateral acid-base sensing through the AE4 to apical pendrin activity.
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Affiliation(s)
- Helga Vitzthum
- Institute of Cellular and Integrative Physiology, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
| | - Catherine Meyer-Schwesinger
- Institute of Cellular and Integrative Physiology, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Heimo Ehmke
- Institute of Cellular and Integrative Physiology, Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
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4
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Dagilgan S, Dundar-Yenilmez E, Tuli A, Urunsak IF, Erdogan S. Acidosis defense mechanisms in the preimplantation stages of embryos in BALB/c strain mice. Theriogenology 2024; 217:136-142. [PMID: 38277795 DOI: 10.1016/j.theriogenology.2024.01.021] [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: 08/22/2023] [Revised: 01/17/2024] [Accepted: 01/17/2024] [Indexed: 01/28/2024]
Abstract
Regulation of intracellular pH (pHi) is an important homeostatic function of cells. There are three major pHi regulatory mechanisms: the HCO3-/Cl- exchanger (AE), which alleviates alkalosis, and the Na+/H+ exchanger (NHE) and Na+,HCO3-/Cl- exchanger (NDBCE), both of which counteract acidosis. NHE activity, which is high at the germinal vesicle stage of oocyte, is inhibited during meiotic maturation, while this inhibition is abolished when the oocyte reaches the pronuclear (PN) stage of the zygote. On the other hand, we have previously found that NDBCE performs complementary regulation against acidosis during meiotic maturation. Additionally, we found that AE activity, which is a defense mechanism against alkalosis, gradually decreases during preimplantation period of embryonic development. Considering that NHE activity is inhibited during meiotic maturation and AE activity gradually decreases during embryonic development stages, we investigated whether NHE and NDBCE activities, both of which act against acidosis, functionally change from the PN zygote to the blastocyst stage of the embryo and identified these pH-regulating proteins at the molecular level in mice of the Balb/c strain. PN zygotes, two-cell (2-c), four-cell (4-c), morula and blastocyst stage embryos were obtained from 5-8-week-old, sexually mature female Balb/c mice by using the classical superovulation procedure. pHi was recorded by using the microspectrofluorometric technique on zygotes and embryos simultaneously loaded with the pH-sensitive fluorophore, 2',7'-Bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF). The activities of NHE and NDBCE were determined from the recovery curve of induced-acidosis in bicarbonate-free and bicarbonate-containing media, respectively. Specific inhibitors such as cariporide (1 μM), S3226 (1 and 10 μM), EIPA (1, 5, and 25 μM), and amiloride (1 mM) were used to functionally identify NHE isoforms, and the nonspecific inhibitor 4,4'-diisocyanatostilbene-2,2' disulphonic acid, disodium salt (DIDS) was used to confirm NDBCE activity. The isoforms of the pHi-regulatory proteins were also identified by molecular biology using real-time PCR. We found that NHE activity was high at all embryonic stages, and differences between stages were not significant. Functional and molecular findings indicated that isoforms of NHE 1 and 5 are present in the blastocyst, whereas isoforms of NHE 1, 3, and 4 are functional at earlier embryonic stages. Although the contribution of NDBCE activity to recovery from induced-acidosis was detected at all embryonic stages, it was significant only in the PN zygote and the 2-c embryo. This finding was confirmed by molecular analysis, which detected the expression of SLC4A8 encoding NDBCE at all embryonic stages. In conclusion, NHE is an active and important defense mechanism against acidosis and is encoded by at least two protein isoforms in all stages of the Balb/c strain of mice. NDBCE has a supportive function in all embryonic stages, especially in the PN zygote and the 2-c embryo. Preimplantation stage embryos have effective mechanisms to defend against acidosis in response to their metabolic end products (increased acid load) and the acidic environment in utero.
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Affiliation(s)
- Senay Dagilgan
- Cukurova University Faculty of Medicine, Departments of Physiology, Balcali, 01330, Adana, Turkey
| | - Ebru Dundar-Yenilmez
- Cukurova University Faculty of Medicine, Biochemistry, Balcali, 01330, Adana, Turkey
| | - Abdullah Tuli
- Cukurova University Faculty of Medicine, Biochemistry, Balcali, 01330, Adana, Turkey
| | - Ibrahim Ferhat Urunsak
- Cukurova University Faculty of Medicine, Obstetric and Gynaecology, Balcali, 01330, Adana, Turkey
| | - Seref Erdogan
- Cukurova University Faculty of Medicine, Departments of Physiology, Balcali, 01330, Adana, Turkey.
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5
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Klaczek CE, Goss GG, Glover CN. Mechanistic characterization of waterborne selenite uptake in the water flea, Daphnia magna, indicates water chemistry affects toxicity in coal mine-impacted waters. CONSERVATION PHYSIOLOGY 2024; 12:coad108. [PMID: 38293640 PMCID: PMC10823350 DOI: 10.1093/conphys/coad108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 11/20/2023] [Accepted: 12/15/2023] [Indexed: 02/01/2024]
Abstract
Concentrations of selenium that exceed regulatory guidelines have been associated with coal mining activities and have been linked to detrimental effects on aquatic ecosystems and the organisms therein. Although the major route of selenium uptake in macroinvertebrates is via the diet, the uptake of waterborne selenite (HSeO3-), the prominent form at circumneutral pH, can be an important contributor to selenium body burden and thus selenium toxicity. In the current study, radiolabelled selenite (Se75) was used to characterize the mechanism of selenite uptake in the water flea, Daphnia magna. The concentration dependence (1-32 μM) of selenite uptake was determined in 1-hour uptake assays in artificial waters that independently varied in bicarbonate, chloride, sulphate, phosphate and selenate concentrations. At concentrations representative of those found in highly contaminated waters, selenite uptake was phosphate-dependent and inhibited by foscarnet, a phosphate transport inhibitor. At higher concentrations, selenite uptake was dependent on waterborne bicarbonate concentration and inhibited by the bicarbonate transporter inhibitor DIDS (4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid). These findings suggest that concentrations of phosphate in coal mining-affected waters could alter selenite uptake in aquatic organisms and could ultimately affect the toxic impacts of selenium in such waters.
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Affiliation(s)
- Chantelle E Klaczek
- Department of Biological Sciences, CW 405 Biological Sciences Bldg., University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Greg G Goss
- Department of Biological Sciences, CW 405 Biological Sciences Bldg., University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Chris N Glover
- Department of Biological Sciences, CW 405 Biological Sciences Bldg., University of Alberta, Edmonton, Alberta T6G 2E9, Canada
- Faculty of Science and Technology and Athabasca River Basin Research Institute, Athabasca University, 1 University Dr., Athabasca, Alberta T9S 3A3, Canada
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6
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Zhang W, Ding D, Lu Y, Chen H, Jiang P, Zuo P, Wang G, Luo J, Yin Y, Luo J, Yin Y. Structural and functional insights into the lipid regulation of human anion exchanger 2. Nat Commun 2024; 15:759. [PMID: 38272905 PMCID: PMC10810954 DOI: 10.1038/s41467-024-44966-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 01/11/2024] [Indexed: 01/27/2024] Open
Abstract
Anion exchanger 2 (AE2) is an electroneutral Na+-independent Cl-/HCO3- exchanger belongs to the SLC4 transporter family. The widely expressed AE2 participates in a variety of physiological processes, including transepithelial acid-base secretion and osteoclastogenesis. Both the transmembrane domains (TMDs) and the N-terminal cytoplasmic domain (NTD) are involved in regulation of AE2 activity. However, the regulatory mechanism remains unclear. Here, we report a 3.2 Å cryo-EM structure of the AE2 TMDs in complex with PIP2 and a 3.3 Å full-length mutant AE2 structure in the resting state without PIP2. We demonstrate that PIP2 at the TMD dimer interface is involved in the substrate exchange process. Mutation in the PIP2 binding site leads to the displacement of TM7 and further stabilizes the interaction between the TMD and the NTD. Reduced substrate transport activity and conformation similar to AE2 in acidic pH indicating the central contribution of PIP2 to the function of AE2.
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Affiliation(s)
- Weiqi Zhang
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Dian Ding
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Yishuo Lu
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Hongyi Chen
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Peijun Jiang
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Peng Zuo
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Guangxi Wang
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Juan Luo
- Institute of Precision Medicine, Peking University Shenzhen Hospital, Shenzhen, 518036, China
| | - Yue Yin
- Department of Pharmacology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Jianyuan Luo
- Department of Medical Genetics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Yuxin Yin
- Institute of Systems Biomedicine, Department of Pathology, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center for Life Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China.
- Institute of Precision Medicine, Peking University Shenzhen Hospital, Shenzhen, 518036, China.
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7
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Nawaly H, Matsui H, Tsuji Y, Iwayama K, Ohashi H, Nakajima K, Matsuda Y. Multiple plasma membrane SLC4s contribute to external HCO3- acquisition during CO2 starvation in the marine diatom Phaeodactylum tricornutum. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:296-307. [PMID: 36124754 DOI: 10.1093/jxb/erac380] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 09/16/2022] [Indexed: 06/15/2023]
Abstract
The availability of CO2 is one of the restrictions on aquatic photosynthesis. Solute carrier (SLC) 4-2, a plasma membrane HCO3- transporter has previously been identified in the marine diatom Phaeodactylum tricornutum. In this study, we discovered two paralogs, PtSLC4-1 and PtSLC4-4, that are both localized at the plasma membrane. Their overexpression stimulated HCO3- uptake, and this was inhibited by the anion channel blocker 4,4´-diisothiocyanostilbene-2,2´-disulfonic (DIDS). Similarly to SLC4-2, PtSLC4-1 specifically required Na+ of ~100 mM for its maximum HCO3- transport activity. Unlike PtSLC4-1 and PtSLC4-2, the HCO3- transport of PtSLC4-4 depended equally on Na+, K+, or Li+, suggesting its broad selectivity for cations. Transcript analyses indicated that PtSLC4-1 was the most abundant HCO3- transporter under CO2 concentrations below atmospheric levels, while PtSLC4-4 showed little transcript induction under atmospheric CO2 but transient induction to comparable levels to PtSLC4-1 during the initial acclimation stage from high CO2 (1%) to very low CO2 (<0.002%). Our results strongly suggest a major HCO3- transport role of PtSLC4-1 with a relatively minor role of PtSLC4-2, and that PtSLC4-4 operates under severe CO2 limitation unselectively to cations when the other SLC4s do not function to support HCO3- uptake.
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Affiliation(s)
- Hermanus Nawaly
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Hiroaki Matsui
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Yoshinori Tsuji
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Kazufumi Iwayama
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Hiroki Ohashi
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Kensuke Nakajima
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Yusuke Matsuda
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
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8
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Wilson AD, Richards MA, Curtis MK, Gunadasa-Rohling M, Monterisi S, Loonat AA, Miller JJ, Ball V, Lewis A, Tyler DJ, Moshnikova A, Andreev OA, Reshetnyak YK, Carr C, Swietach P. Acidic environments trigger intracellular H+-sensing FAK proteins to re-balance sarcolemmal acid-base transporters and auto-regulate cardiomyocyte pH. Cardiovasc Res 2022; 118:2946-2959. [PMID: 34897412 PMCID: PMC9648823 DOI: 10.1093/cvr/cvab364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/08/2021] [Indexed: 11/12/2022] Open
Abstract
AIMS In cardiomyocytes, acute disturbances to intracellular pH (pHi) are promptly corrected by a system of finely tuned sarcolemmal acid-base transporters. However, these fluxes become thermodynamically re-balanced in acidic environments, which inadvertently causes their set-point pHi to fall outside the physiological range. It is unclear whether an adaptive mechanism exists to correct this thermodynamic challenge, and return pHi to normal. METHODS AND RESULTS Following left ventricle cryo-damage, a diffuse pattern of low extracellular pH (pHe) was detected by acid-sensing pHLIP. Despite this, pHi measured in the beating heart (13C NMR) was normal. Myocytes had adapted to their acidic environment by reducing Cl-/HCO3- exchange (CBE)-dependent acid-loading and increasing Na+/H+ exchange (NHE1)-dependent acid-extrusion, as measured by fluorescence (cSNARF1). The outcome of this adaptation on pHi is revealed as a cytoplasmic alkalinization when cells are superfused at physiological pHe. Conversely, mice given oral bicarbonate (to improve systemic buffering) had reduced myocardial NHE1 expression, consistent with a needs-dependent expression of pHi-regulatory transporters. The response to sustained acidity could be replicated in vitro using neonatal ventricular myocytes incubated at low pHe for 48 h. The adaptive increase in NHE1 and decrease in CBE activities was linked to Slc9a1 (NHE1) up-regulation and Slc4a2 (AE2) down-regulation. This response was triggered by intracellular H+ ions because it persisted in the absence of CO2/HCO3- and became ablated when acidic incubation media had lower chloride, a solution manoeuvre that reduces the extent of pHi-decrease. Pharmacological inhibition of FAK-family non-receptor kinases, previously characterized as pH-sensors, ablated this pHi autoregulation. In support of a pHi-sensing role, FAK protein Pyk2 (auto)phosphorylation was reduced within minutes of exposure to acidity, ahead of adaptive changes to pHi control. CONCLUSIONS Cardiomyocytes fine-tune the expression of pHi-regulators so that pHi is at least 7.0. This autoregulatory feedback mechanism defines physiological pHi and protects it during pHe vulnerabilities.
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Affiliation(s)
- Abigail D Wilson
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Mark A Richards
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - M Kate Curtis
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Mala Gunadasa-Rohling
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Stefania Monterisi
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Aminah A Loonat
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Jack J Miller
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, UK
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Vicky Ball
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Andrew Lewis
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Damian J Tyler
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, Level 0, John Radcliffe Hospital, Headington, Oxford OX3 9DU, UK
| | - Anna Moshnikova
- Physics Department, University of Rhode Island, 2 Lippitt Rd, Kingston, RI 02881, USA
| | - Oleg A Andreev
- Physics Department, University of Rhode Island, 2 Lippitt Rd, Kingston, RI 02881, USA
| | - Yana K Reshetnyak
- Physics Department, University of Rhode Island, 2 Lippitt Rd, Kingston, RI 02881, USA
| | - Carolyn Carr
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Pawel Swietach
- Department of Physiology, Anatomy & Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
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9
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Cheng WY, Yang SY, Huang XY, Zi FY, Li HP, Sheng XL. Identification of genetic variants in five chinese families with keratoconus: Pathogenicity analysis and characteristics of parental corneal topography. Front Genet 2022; 13:978684. [PMID: 36276932 PMCID: PMC9583916 DOI: 10.3389/fgene.2022.978684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 09/12/2022] [Indexed: 12/02/2022] Open
Abstract
Purpose: The study aims to identify genetic variants in five Chinese families with Keratoconus (KC) and describe the characteristics of parental corneal topography. Methods: Fifteen participants, including five probands and ten parents from five Chinese families with KC, were recruited for genetic and clinical analyses. Targeted next-generation sequencing using a custom-designed panel for KC was applied on the probands for variant identification. Sanger sequencing and cosegregation analysis of the suspected pathogenic variants were performed on the family members. The pathogenicities of variants were evaluated according to the American College of Medical Genetics and Genomics guidelines (ACMG). Pentacam 3D anterior segment analysis system was applied for keratectasia detection and the Corvis ST for corneal biomechanics measurement. Fifteen parameters were recorded, including nine keratectasia indicators (BAD-D, TP, Kmax, Df, Db, Dp, Dt, Da, ARTH), six corneal biomechanical indicators (CBI, DA ratio, SP-A1, IR, bIOP, TBI). Results: A total of six novel variants, including five missense variants and one frameshift variant, were detected in the HMX1, SLC4A11, TGFBI, PIKFYVE, and ZEB1 genes in five probands, all of which showed co-segregation of genotype and clinical phenotype and were determined to be pathogenic. The genetic model was autosomal dominant (AD) in four families and autosomal recessive (AR) in 1 family. The analysis of keratectasia and corneal biomechanical indicators of the proband’s parents (first-generation relatives) in AD families revealed that there were several abnormal indexes in BAD-D, TP, Kmax, Df, Db, Dp, Dt, Da, CBI, DA ratio, SP-A1, IR, bIOP and TBI test indexes, showing clinical characteristics of incipient KC. Conclusion: Our study shows that variants in HMX1, SLC4A11, TGFBI, PIKFYVE, and ZEB1 were associated with KC. Our study extends the gene spectrum associated with KC, provides novel insights into KC phenotypic assessments, and contributes to early diagnosis for these patients.
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Affiliation(s)
- Wan-Yu Cheng
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, Yinchuan, China
| | - Shang-Ying Yang
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, Yinchuan, China
| | - Xiao-Yu Huang
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, Yinchuan, China
| | - Fei-Yin Zi
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, Yinchuan, China
| | - Hui-Ping Li
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Third Clinical Medical College of Ningxia Medical University, Yinchuan, China
- *Correspondence: Hui-Ping Li, ; Xun-Lun Sheng,
| | - Xun-Lun Sheng
- Gansu Aier Ophthalmology and Optometry Hospital, Lanzhou City, China
- *Correspondence: Hui-Ping Li, ; Xun-Lun Sheng,
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10
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Wang J, Zahra A, Wang Y, Wu J. Understanding the Physiological Role of Electroneutral Na+-Coupled HCO3− Cotransporter and Its Therapeutic Implications. Pharmaceuticals (Basel) 2022; 15:ph15091082. [PMID: 36145304 PMCID: PMC9505461 DOI: 10.3390/ph15091082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Acid–base homeostasis is critical for proper physiological function and pathology. The SLC4 family of HCO3− transmembrane cotransporters is one of the HCO3− transmembrane transport carriers responsible for cellular pH regulation and the uptake or secretion of HCO3− in epithelial cells. NBCn1 (SLC4A7), an electroneutral Na+/HCO3− cotransporter, is extensively expressed in several tissues and functions as a cotransporter for net acid extrusion after cellular acidification. However, the expression and activity level of NBCn1 remain elusive. In addition, NBCn1 has been involved in numerous other cellular processes such as cell volume, cell death/survival balance, transepithelial transport, as well as regulation of cell viability. This review aims to give an inclusive overview of the most recent advances in the research of NBCn1, emphasizing the basic features, regulation, and tissue-specific physiology as well as the development and application of potent inhibitors of NBCn1 transporter in cancer therapy. Research and development of targeted therapies should be carried out for NBCn1 and its associated pathways.
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Affiliation(s)
- Jingjing Wang
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China
| | - Aqeela Zahra
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China
| | - YunFu Wang
- Hubei Key Laboratory of Embryonic Stem Cell Research, Hubei University of Medicine, Shiyan 442000, China
| | - Jianping Wu
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China
- Hubei Key Laboratory of Embryonic Stem Cell Research, Hubei University of Medicine, Shiyan 442000, China
- Correspondence:
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11
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Tian F, Liu S, Zhou B, Tang Y, Zhang Y, Zhang C, Zhao K. Chromosome-level genome of Tibetan naked carp ( Gymnocypris przewalskii) provides insights into Tibetan highland adaptation. DNA Res 2022; 29:6647840. [PMID: 35861387 PMCID: PMC9326183 DOI: 10.1093/dnares/dsac025] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
Gymnocypris przewalskii, a cyprinid fish endemic to the Qinghai-Tibetan Plateau, has evolved unique morphological, physiological and genetic characteristics to adapt to the highland environment. Herein, we assembled a high-quality G. przewalskii tetraploid genome with a size of 2.03 Gb and scaffold N50 of 44.93 Mb, which was anchored onto 46 chromosomes. The comparative analysis suggested that gene families related to highland adaptation were significantly expanded in G. przewalskii. According to the G. przewalskii genome, we evaluated the phylogenetic relationship of 13 schizothoracine fishes, and inferred that the demographic history of G. przewalskii was strongly associated with geographic and eco-environmental alterations. We noticed that G. przewalskii experienced whole-genome duplication, and genes preserved post duplication were functionally associated with adaptation to high salinity and alkalinity. In conclusion, a chromosome-scale G. przewalskii genome provides an important genomic resource for teleost fish, and will particularly promote our understanding of the molecular evolution and speciation of fish in the highland environment.
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Affiliation(s)
- Fei Tian
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
- University of Chinese Academy of Sciences , Beijing, China
| | - Sijia Liu
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
| | - Bingzheng Zhou
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
- University of Chinese Academy of Sciences , Beijing, China
| | - Yongtao Tang
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
- Henan Normal University , Xinxiang, China
| | - Yu Zhang
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
- University of Chinese Academy of Sciences , Beijing, China
| | - Cunfang Zhang
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University , Xining, Qinghai, China
| | - Kai Zhao
- Qinghai Provincial Key Laboratory of Animal Ecological Genomics, Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences , Xining, Qinghai, China
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12
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Ji M, Ryu HJ, Baek HM, Shin DM, Hong JH. Dynamic synovial fibroblasts are modulated by NBCn1 as a potential target in rheumatoid arthritis. Exp Mol Med 2022; 54:503-517. [PMID: 35414711 PMCID: PMC9076869 DOI: 10.1038/s12276-022-00756-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 01/09/2022] [Accepted: 01/26/2022] [Indexed: 11/09/2022] Open
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease characterized by aggressive fibroblast-like synoviocytes (FLSs) and pannus formation. Various therapeutic strategies have been developed against inflammatory cytokines in RA in recent decades. Based on the migratory features of FLSs, we examined whether modulation of the migratory module attenuates RA severity. In this study, inflamed synovial fluid-stimulated FLSs exhibited enhanced migration and migratory apparatus expression, and sodium bicarbonate cotransporter n1 (NBCn1) was identified in primary cultured RA-FLSs for the first time. The NBC inhibitor S0859 attenuated the migration of FLSs induced with synovial fluid from patients with RA or with TNF-α stimulation. Inhibition of NBCs with S0859 in a collagen-induced arthritis (CIA) mouse model reduced joint swelling and destruction without blood, hepatic, or renal toxicity. Primary FLSs isolated from the CIA-induced mouse model also showed reduced migration in the presence of S0859. Our results suggest that inflammatory mediators in synovial fluid, including TNF-α, recruit NBCn1 to the plasma membrane of FLSs to provide dynamic properties and that modulation of NBCn1 could be developed into a therapeutic strategy for RA.
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Affiliation(s)
- Minjeong Ji
- Department of Physiology, College of Medicine, Gachon University, Lee Gil Ya Cancer and Diabetes Institute, 155 Getbeolro, Yeonsu-gu, Incheon, South Korea
- Department of Oral Biology, Yonsei University College of Dentistry, Seoul, South Korea
| | - Hee Jung Ryu
- Division of Rheumatology, Department of Internal Medicine, Gachon University Gil Medical Center, 21 Namdongdae-ro 774-gil, Nandong-gu, Incheon, South Korea
| | - Hyeon-Man Baek
- Department of Health Sciences and Technology, GAIHST, Gachon University, Incheon, South Korea
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 155 Getbeolro, Yeonsu-gu, Incheon, South Korea
| | - Dong Min Shin
- Department of Oral Biology, Yonsei University College of Dentistry, Seoul, South Korea.
| | - Jeong Hee Hong
- Department of Physiology, College of Medicine, Gachon University, Lee Gil Ya Cancer and Diabetes Institute, 155 Getbeolro, Yeonsu-gu, Incheon, South Korea.
- Department of Health Sciences and Technology, GAIHST, Gachon University, Incheon, South Korea.
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 155 Getbeolro, Yeonsu-gu, Incheon, South Korea.
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13
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Collin GB, Shi L, Yu M, Akturk N, Charette JR, Hyde LF, Weatherly SM, Pera MF, Naggert JK, Peachey NS, Nishina PM, Krebs MP. A Splicing Mutation in Slc4a5 Results in Retinal Detachment and Retinal Pigment Epithelium Dysfunction. Int J Mol Sci 2022; 23:2220. [PMID: 35216333 PMCID: PMC8875008 DOI: 10.3390/ijms23042220] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 02/13/2022] [Accepted: 02/14/2022] [Indexed: 12/29/2022] Open
Abstract
Fluid and solute transporters of the retinal pigment epithelium (RPE) are core components of the outer blood-retinal barrier. Characterizing these transporters and their role in retinal homeostasis may provide insights into ocular function and disease. Here, we describe RPE defects in tvrm77 mice, which exhibit hypopigmented patches in the central retina. Mapping and nucleotide sequencing of tvrm77 mice revealed a disrupted 5' splice donor sequence in Slc4a5, a sodium bicarbonate cotransporter gene. Slc4a5 expression was reduced 19.7-fold in tvrm77 RPE relative to controls, and alternative splice variants were detected. SLC4A5 was localized to the Golgi apparatus of cultured human RPE cells and in apical and basal membranes. Fundus imaging, optical coherence tomography, microscopy, and electroretinography (ERG) of tvrm77 mice revealed retinal detachment, hypopigmented patches corresponding to neovascular lesions, and retinal folds. Detachment worsened and outer nuclear layer thickness decreased with age. ERG a- and b-wave response amplitudes were initially normal but declined in older mice. The direct current ERG fast oscillation and light peak were reduced in amplitude at all ages, whereas other RPE-associated responses were unaffected. These results link a new Slc4a5 mutation to subretinal fluid accumulation and altered light-evoked RPE electrophysiological responses, suggesting that SLC4A5 functions at the outer blood-retinal barrier.
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Affiliation(s)
- Gayle B. Collin
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Lanying Shi
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Minzhong Yu
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA; (M.Y.); (N.S.P.)
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Nurten Akturk
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Jeremy R. Charette
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Lillian F. Hyde
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Sonia M. Weatherly
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Martin F. Pera
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Jürgen K. Naggert
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Neal S. Peachey
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA; (M.Y.); (N.S.P.)
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, 9500 Euclid Avenue, Cleveland, OH 44195, USA
- Research Service, Louis Stokes Cleveland VA Medical Center, 10701 East Boulevard, Cleveland, OH 44106, USA
| | - Patsy M. Nishina
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
| | - Mark P. Krebs
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA; (G.B.C.); (L.S.); (N.A.); (J.R.C.); (L.F.H.); (S.M.W.); (M.F.P.); (J.K.N.)
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14
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Klett NJ, Cravetchi O, Allen CN. Long-Term Imaging Reveals a Circadian Rhythm of Intracellular Chloride in Neurons of the Suprachiasmatic Nucleus. J Biol Rhythms 2022; 37:110-123. [PMID: 34994231 DOI: 10.1177/07487304211059770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Both inhibitory and excitatory GABA transmission exist in the mature suprachiasmatic nucleus (SCN), the master pacemaker of circadian physiology. Whether GABA is inhibitory or excitatory depends on the intracellular chloride concentration ([Cl-]i). Here, using the genetically encoded ratiometric probe Cl-Sensor, we investigated [Cl-]i in AVP and VIP-expressing SCN neurons for several days in culture. The chloride ratio (RCl) demonstrated circadian rhythmicity in AVP + neurons and VIP + neurons, but was not detected in GFAP + astrocytes. RCl peaked between ZT 7 and ZT 8 in both AVP + and VIP + neurons. RCl rhythmicity was not dependent on the activity of several transmembrane chloride carriers, action potential generation, or the L-type voltage-gated calcium channels, but was sensitive to GABA antagonists. We conclude that [Cl-]i is under circadian regulation in both AVP + and VIP + neurons.
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Affiliation(s)
- Nathan J Klett
- Neuroscience Graduate Program, Oregon Health & Science University, Portland, Oregon, USA.,Oregon Institute for Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon, USA.,Neurophysiology, Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Olga Cravetchi
- Oregon Institute for Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon, USA
| | - Charles N Allen
- Oregon Institute for Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon, USA.,Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
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15
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Du L, Zahra A, Jia M, Wang Q, Wu J. Understanding the Functional Expression of Na+-Coupled SLC4 Transporters in the Renal and Nervous Systems: A Review. Brain Sci 2021; 11:1276. [PMID: 34679341 PMCID: PMC8534249 DOI: 10.3390/brainsci11101276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/16/2021] [Accepted: 09/23/2021] [Indexed: 11/25/2022] Open
Abstract
Acid-base homeostasis is crucial for numerous physiological processes. Na+/HCO3- cotransporters (NBCs) belong to the solute carrier 4 (SLC4) family, which regulates intracellular pH as well as HCO3- absorption and secretion. However, knowledge of the structural functions of these proteins remains limited. Electrogenic NBC (NBCe-1) is thought to be the primary factor promoting the precise acid-base equilibrium in distinct cell types for filtration and reabsorption, as well as the function of neurons and glia. NBC dysregulation is strongly linked to several diseases. As such, the need for special drugs that interfere with the transmission function of NBC is becoming increasingly urgent. In this review, we focus on the structural and functional characteristics of NBCe1, and discuss the roles of NBCe1 in the kidney, central nervous system (CNS), and related disorders, we also summarize the research on NBC inhibitors. NBCe1 and the related pathways should be further investigated, so that new medications may be developed to address the related conditions.
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Affiliation(s)
- Le Du
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (L.D.); (A.Z.)
| | - Aqeela Zahra
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (L.D.); (A.Z.)
| | - Meng Jia
- Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China; (M.J.); (Q.W.)
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100070, China
- National Clinical Research Center for Neurological Disease, Beijing 100070, China
| | - Qun Wang
- Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China; (M.J.); (Q.W.)
- National Clinical Research Center for Neurological Disease, Beijing 100070, China
| | - Jianping Wu
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, China; (L.D.); (A.Z.)
- Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China; (M.J.); (Q.W.)
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing 100070, China
- National Clinical Research Center for Neurological Disease, Beijing 100070, China
- Health Science Center, Yangtze University, Jingzhou 434023, China
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16
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Zhou C, Hu B, Tang Y, Yang C, Ma W, Wang X, Liu R, Yan X, Dong J, Wang X, Nie G. The Chromosome-Level Genome of Triplophysa dalaica (Cypriniformes: Cobitidae) Provides Insights into Its Survival in Extremely Alkaline Environment. Genome Biol Evol 2021; 13:evab153. [PMID: 34185063 PMCID: PMC8358222 DOI: 10.1093/gbe/evab153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2021] [Indexed: 12/24/2022] Open
Abstract
Lake Dali Nur, located in Inner Mongolia, North China, is alkaline, with Triplophysa dalaica one of the three fish species that not only survive, but thrive, in the lake. To investigate the presence of molecular mutations potentially responsible for this adaptation, the whole-genome sequence of the species was sequenced. A total of 126.5 and 106 Gb data, covering nearly 200× of the estimated genome, were generated using long-read sequencing and Hi-C technology, respectively. De novo assembly generated a genome totalled 607.91 Mb, with a contig N50 of 9.27 Mb. Nearly all whole-genome sequences were anchored and oriented onto 25 chromosomes, with telomeres for most chromosomes also being recovered. Repeats comprised approximately 35.01% of the whole genome. A total of 23,925 protein-coding genes were predicted, within which, 98.62% could be functionally annotated. Through comparisons of T. dalaica, T. tibetana, and T. siluroides gene models, a total of 898 genes were identified as likely being subjected to positive selection, with several of them potentially associated with alkaline adaptation, such as sodium bicarbonate cotransporter, SLC4A4. Demographic analyses suggested that the Dali population might have diverged from endemic freshwater Hai River populations, approximately 1 Ma. The high-quality T. dalaica genome, created in this study, not only aids in the analyses of alkaline adaptation, but may also assist in revealing the mysteries of the highly divergent genus Triplophysa in the future.
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Affiliation(s)
- Chuanjiang Zhou
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Bo Hu
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Yongtao Tang
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Changxing Yang
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Wenwen Ma
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Xi Wang
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Ruyao Liu
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Xuemeng Yan
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Jing Dong
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Xianfeng Wang
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
| | - Guoxing Nie
- College of Fisheries, Engineering Technology Research Center of Henan Province for Aquatic Animal Cultivation, Henan Normal University, Xinxiang, Henan, China
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17
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Nolly MB, Vargas LA, Correa MV, Lofeudo JM, Pinilla AO, Rueda JOV, Guerrero-Gimenez ME, Swenson ER, Damiani MT, Alvarez BV. Carbonic anhydrase IX and hypoxia-inducible factor 1 attenuate cardiac dysfunction after myocardial infarction. Pflugers Arch 2021; 473:1273-1285. [PMID: 34231059 DOI: 10.1007/s00424-021-02592-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 01/11/2023]
Abstract
Myocardial infarction (MI) is one of the leading causes of death worldwide. Prognosis and mortality rate are directly related to infarct size and post-infarction pathological heart remodeling, which can lead to heart failure. Hypoxic MI-affected areas increase the expression of hypoxia-inducible factor (HIF-1), inducing infarct size reduction and improving cardiac function. Hypoxia translocates HIF-1 to the nucleus, activating carbonic anhydrase IX (CAIX) transcription. CAIX regulates myocardial intracellular pH, critical for heart performance. Our objective was to investigate CAIX participation and relation with sodium bicarbonate transporters 1 (NBC1) and HIF-1 in cardiac remodeling after MI. We analyzed this pathway in an "in vivo" rat coronary artery ligation model and isolated cardiomyocytes maintained under hypoxia. Immunohistochemical studies revealed an increase in HIF-1 levels after 2 h of infarction. Similar results were observed in 2-h infarcted cardiac tissue (immunoblotting) and in hypoxic cardiomyocytes with a nuclear distribution (confocal microscopy). Immunohistochemical studies showed an increase CAIX in the infarcted area at 2 h, mainly distributed throughout the cell and localized in the plasma membrane at 24 h. Similar results were observed in 2 h in infarcted cardiac tissue (immunoblotting) and in hypoxic cardiomyocytes (confocal microscopy). NBC1 expression increased in cardiac tissue after 2 h of infarction (immunoblotting). CAIX and NBC1 interaction increases in cardiac tissue subjected to MI for 2h when CAIX is present (immunoprecipitation). These results suggest that CAIX interacts with NBC1 in our infarct model as a mechanism to prevent acidic damage in hypoxic tissue, making it a promising therapeutic target.
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Affiliation(s)
- Mariela Beatriz Nolly
- Laboratorio de Bioquímica e Inmunidad, IMBECU-CONICET-UNCuyo, Instituto de Bioquímica y Biotecnología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500, Mendoza, Argentina.
| | - Lorena Alejandra Vargas
- Centro de Investigaciones Cardiovasculares, CIC-CONICET, Facultad de Medicina, Universidad Nacional de La Plata, La Plata, 1900, Buenos Aires, Argentina
| | - María Verónica Correa
- Comisión de Investigaciones Científicas de la Provincia de Buenos Aires, CIC-PBA, La Plata, 1900, Buenos Aires, Argentina
| | - Juan Manuel Lofeudo
- Centro de Investigaciones Cardiovasculares, CIC-CONICET, Facultad de Medicina, Universidad Nacional de La Plata, La Plata, 1900, Buenos Aires, Argentina
| | - Andrés Oscar Pinilla
- Centro de Investigaciones Cardiovasculares, CIC-CONICET, Facultad de Medicina, Universidad Nacional de La Plata, La Plata, 1900, Buenos Aires, Argentina
| | - Jorge Omar Velez Rueda
- Centro de Investigaciones Cardiovasculares, CIC-CONICET, Facultad de Medicina, Universidad Nacional de La Plata, La Plata, 1900, Buenos Aires, Argentina
| | - Martin E Guerrero-Gimenez
- Laboratorio de Oncología, IMBECU-CONICET-UNCuyo, Instituto de Bioquímica y Biotecnología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500, Mendoza, Argentina
| | - Erik Richard Swenson
- Medical Service, VA Puget Sound Health Care System, University of Washington, Seattle, WA, USA
| | - Maria Teresa Damiani
- Laboratorio de Bioquímica e Inmunidad, IMBECU-CONICET-UNCuyo, Instituto de Bioquímica y Biotecnología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500, Mendoza, Argentina
| | - Bernardo Victor Alvarez
- Centro de Investigaciones Cardiovasculares, CIC-CONICET, Facultad de Medicina, Universidad Nacional de La Plata, La Plata, 1900, Buenos Aires, Argentina
- Department of Biochemistry, Membrane Protein Disease Research Group, University of Alberta, Edmonton, Alberta, T6G 2H7, Canada
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18
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Khosrowabadi E, Rivinoja A, Risteli M, Tuomisto A, Salo T, Mäkinen MJ, Kellokumpu S. SLC4A2 anion exchanger promotes tumour cell malignancy via enhancing net acid efflux across golgi membranes. Cell Mol Life Sci 2021; 78:6283-6304. [PMID: 34279699 PMCID: PMC8429400 DOI: 10.1007/s00018-021-03890-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 06/08/2021] [Accepted: 06/25/2021] [Indexed: 12/27/2022]
Abstract
Proper functioning of each secretory and endocytic compartment relies on its unique pH micro-environment that is known to be dictated by the rates of V-ATPase-mediated H+ pumping and its leakage back to the cytoplasm via an elusive "H+ leak" pathway. Here, we show that this proton leak across Golgi membranes is mediated by the AE2a (SLC4A2a)-mediated bicarbonate-chloride exchange, as it is strictly dependent on bicarbonate import (in exchange for chloride export) and the expression level of the Golgi-localized AE2a anion exchanger. In the acidic Golgi lumen, imported bicarbonate anions and protons then facilitate a common buffering reaction that yields carbon dioxide and water before their egress back to the cytoplasm via diffusion or water channels. The flattened morphology of the Golgi cisternae helps this process, as their high surface-volume ratio is optimal for water and gas exchange. Interestingly, this net acid efflux pathway is often upregulated in cancers and established cancer cell lines, and responsible for their markedly elevated Golgi resting pH and attenuated glycosylation potential. Accordingly, AE2 knockdown in SW-48 colorectal cancer cells was able to restore these two phenomena, and at the same time, reverse their invasive and anchorage-independent growth phenotype. These findings suggest a possibility to return malignant cells to a benign state by restoring Golgi resting pH.
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Affiliation(s)
- Elham Khosrowabadi
- Faculty of Biochemistry and Molecular Medicine, University of Oulu (Oulun Yliopisto), Aapistie 7A, PO BOX 5400, 90014, Oulu, Finland.
| | | | - Maija Risteli
- Cancer and Translational Medicine Research Unit, University of Oulu, Oulu, Finland.,Medical Research Centre, Oulu University Hospital, Oulu, Finland
| | - Anne Tuomisto
- Medical Research Centre, Oulu University Hospital, Oulu, Finland
| | - Tuula Salo
- Cancer and Translational Medicine Research Unit, University of Oulu, Oulu, Finland.,Medical Research Centre, Oulu University Hospital, Oulu, Finland
| | - Markus J Mäkinen
- Medical Research Centre, Oulu University Hospital, Oulu, Finland
| | - Sakari Kellokumpu
- Faculty of Biochemistry and Molecular Medicine, University of Oulu (Oulun Yliopisto), Aapistie 7A, PO BOX 5400, 90014, Oulu, Finland.
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19
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Toft NJ, Axelsen TV, Pedersen HL, Mele M, Burton M, Balling E, Johansen T, Thomassen M, Christiansen PM, Boedtkjer E. Acid-base transporters and pH dynamics in human breast carcinomas predict proliferative activity, metastasis, and survival. eLife 2021; 10:68447. [PMID: 34219652 PMCID: PMC8282339 DOI: 10.7554/elife.68447] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 07/02/2021] [Indexed: 12/13/2022] Open
Abstract
Breast cancer heterogeneity in histology and molecular subtype influences metabolic and proliferative activity and hence the acid load on cancer cells. We hypothesized that acid-base transporters and intracellular pH (pHi) dynamics contribute inter-individual variability in breast cancer aggressiveness and prognosis. We show that Na+,HCO3- cotransport and Na+/H+ exchange dominate cellular net acid extrusion in human breast carcinomas. Na+/H+ exchange elevates pHi preferentially in estrogen receptor-negative breast carcinomas, whereas Na+,HCO3- cotransport raises pHi more in invasive lobular than ductal breast carcinomas and in higher malignancy grade breast cancer. HER2-positive breast carcinomas have elevated protein expression of Na+/H+ exchanger NHE1/SLC9A1 and Na+,HCO3- cotransporter NBCn1/SLC4A7. Increased dependency on Na+,HCO3- cotransport associates with severe breast cancer: enlarged CO2/HCO3--dependent rises in pHi predict accelerated cell proliferation, whereas enhanced CO2/HCO3--dependent net acid extrusion, elevated NBCn1 protein expression, and reduced NHE1 protein expression predict lymph node metastasis. Accordingly, we observe reduced survival for patients suffering from luminal A or basal-like/triple-negative breast cancer with high SLC4A7 and/or low SLC9A1 mRNA expression. We conclude that the molecular mechanisms of acid-base regulation depend on clinicopathological characteristics of breast cancer patients. NBCn1 expression and dependency on Na+,HCO3- cotransport for pHi regulation, measured in biopsies of human primary breast carcinomas, independently predict proliferative activity, lymph node metastasis, and patient survival.
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Affiliation(s)
- Nicolai J Toft
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Trine V Axelsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Helene L Pedersen
- Department of Pathology, Regionshospitalet Randers, Randers, Denmark
| | - Marco Mele
- Department of Surgery, Regionshospitalet Randers, Randers, Denmark
| | - Mark Burton
- Department of Clinical Genetics, University of Southern Denmark, Odense, Denmark.,Clinical Genome Center, University and Region of Southern Denmark, Odense, Denmark
| | - Eva Balling
- Department of Surgery, Regionshospitalet Randers, Randers, Denmark
| | - Tonje Johansen
- Department of Pathology, Regionshospitalet Randers, Randers, Denmark
| | - Mads Thomassen
- Department of Clinical Genetics, University of Southern Denmark, Odense, Denmark.,Clinical Genome Center, University and Region of Southern Denmark, Odense, Denmark
| | - Peer M Christiansen
- Department of Surgery, Regionshospitalet Randers, Randers, Denmark.,Department of Plastic and Breast Surgery, Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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20
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Abehsera S, Bentov S, Li X, Weil S, Manor R, Sagi S, Li S, Li F, Khalaila I, Aflalo ED, Sagi A. Genes encoding putative bicarbonate transporters as a missing molecular link between molt and mineralization in crustaceans. Sci Rep 2021; 11:11722. [PMID: 34083647 PMCID: PMC8175698 DOI: 10.1038/s41598-021-91155-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 05/17/2021] [Indexed: 01/08/2023] Open
Abstract
During their life, crustaceans undergo several molts, which if theoretically compared to the human body would be equivalent to replacing all bones at a single event. Such a dramatic repetitive event is coupled to unique molecular mechanisms of mineralization so far mostly unknown. Unlike human bone mineralized with calcium phosphate, the crustacean exoskeleton is mineralized mainly by calcium carbonate. Crustacean growth thus necessitates well-timed mobilization of bicarbonate to specific extracellular sites of biomineralization at distinct molt cycle stages. Here, by looking at the crayfish Cherax quadricarinatus at different molting stages, we suggest that the mechanisms of bicarbonate ion transport for mineralization in crustaceans involve the SLC4 family of transporters and that these proteins play a key role in the tight coupling between molt cycle events and mineral deposition. This discovery of putative bicarbonate transporters in a pancrustacean with functional genomic evidence from genes encoding the SLC4 family-mostly known for their role in pH control-is discussed in the context of the evolution of calcium carbonate biomineralization.
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Affiliation(s)
- Shai Abehsera
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Shmuel Bentov
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Xuguang Li
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, People's Republic of China
| | - Simy Weil
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Rivka Manor
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Shahar Sagi
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel
| | - Shihao Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, People's Republic of China
| | - Fuhua Li
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, People's Republic of China
| | - Isam Khalaila
- Department of Biotechnology Engineering, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Eliahu D Aflalo
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel
- Department of Life Sciences, Achva Academic College, Arugot, Israel
| | - Amir Sagi
- Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, 8410501, Beer Sheva, Israel.
- The National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
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21
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Nielsen MMK, Aryal E, Safari E, Mojsoska B, Jenssen H, Prabhala BK. Current State of SLC and ABC Transporters in the Skin and Their Relation to Sweat Metabolites and Skin Diseases. Proteomes 2021; 9:proteomes9020023. [PMID: 34065737 PMCID: PMC8163169 DOI: 10.3390/proteomes9020023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/11/2021] [Accepted: 05/13/2021] [Indexed: 01/02/2023] Open
Abstract
With a relatively large surface area (2 m2) and 15% of total body mass, the skin forms the largest organ of the human body. The main functions of the skin include regulation of body temperature by insulation or sweating, regulation of the nervous system, regulation of water content, and protection against external injury. To perform these critical functions, the skin encodes genes for transporters responsible for the cellular trafficking of essential nutrients and metabolites to maintain cellular hemostasis. However, the knowledge on the expression, regulation, and function of these transporters is very limited and needs more work to elucidate how these transporters play a role both in disease progression and in healing. Furthermore, SLC and ABC transporters are understudied, and even less studied in skin. There are sparse reports on relation between transporters in skin and sweat metabolites. This mini review focuses on the current state of SLC and ABC transporters in the skin and their relation to sweat metabolites and skin diseases.
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Affiliation(s)
- Marcus M. K. Nielsen
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark; (M.M.K.N.); (E.A.)
| | - Eva Aryal
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark; (M.M.K.N.); (E.A.)
| | - Elnaz Safari
- Department of Organic Chemistry, Faculty of Chemistry, Urmia University, Urmia 5756151818, Iran;
| | - Biljana Mojsoska
- Institute of Science and Environment, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark; (B.M.); (H.J.)
| | - Håvard Jenssen
- Institute of Science and Environment, Roskilde University, Universitetsvej 1, 4000 Roskilde, Denmark; (B.M.); (H.J.)
| | - Bala Krishna Prabhala
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark; (M.M.K.N.); (E.A.)
- Correspondence:
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22
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Lin HY, Huang RC. Glycolytic metabolism and activation of Na + pumping contribute to extracellular acidification in the central clock of the suprachiasmatic nucleus: Differential glucose sensitivity and utilization between oxidative and non-oxidative glycolytic pathways. Biomed J 2021; 45:143-154. [PMID: 35341719 PMCID: PMC9133309 DOI: 10.1016/j.bj.2021.02.004] [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: 11/03/2020] [Revised: 02/02/2021] [Accepted: 02/07/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The central clock of the suprachiasmatic nucleus (SCN) controls the metabolism of glucose and is sensitive to glucose shortage. However, it is only beginning to be understood how metabolic signals such as glucose availability regulate the SCN physiology. We previously showed that the ATP-sensitive K+ channel plays a glucose-sensing role in regulating SCN neuronal firing at times of glucose shortage. Nevertheless, it is unknown whether the energy-demanding Na+/K+-ATPase (NKA) is also sensitive to glucose availability. Furthermore, we recently showed that the metabolically active SCN constantly extrudes H+ to acidify extracellular pH (pHe). This study investigated whether the standing acidification is associated with Na+ pumping activity, energy metabolism, and glucose utilization, and whether glycolysis- and mitochondria-fueled NKAs may be differentially sensitive to glucose shortage. METHODS Double-barreled pH-selective microelectrodes were used to determine the pHe in the SCN in hypothalamic slices. RESULTS NKA inhibition with K+-free (0-K+) solution rapidly and reversibly alkalinized the pHe, an effect abolished by ouabain. Mitochondrial inhibition with cyanide acidified the pHe but did not inhibit 0-K+-induced alkalinization. Glycolytic inhibition with iodoacetate alkalinized the pHe, completely blocked cyanide-induced acidification, and nearly completely blocked 0-K+-induced alkalinization. The results indicate that glycolytic metabolism and activation of Na+ pumping contribute to the standing acidification. Glucoprivation also alkalinized the pHe, nearly completely eliminated cyanide-induced acidification, but only partially reduced 0-K+-induced alkalinization. In contrast, hypoglycemia preferentially and partially blocked cyanide-induced acidification. The result indicates sensitivity to glucose shortage for the mitochondria-associated oxidative glycolytic pathway. CONCLUSION Glycolytic metabolism and activation of glycolysis-fueled NKA Na+ pumping activity contribute to the standing acidification in the SCN. Furthermore, the oxidative and non-oxidative glycolytic pathways differ in their glucose sensitivity and utilization, with the oxidative glycolytic pathway susceptible to glucose shortage, and the non-oxidative glycolytic pathway able to maintain Na+ pumping even in glucoprivation.
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Affiliation(s)
- Hsin-Yi Lin
- Department of Physiology and Pharmacology, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Rong-Chi Huang
- Department of Physiology and Pharmacology, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Healthy Aging Research Center, Chang Gung University, Taoyuan, Taiwan; Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
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23
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Wang J, Wang W, Wang H, Tuo B. Physiological and Pathological Functions of SLC26A6. Front Med (Lausanne) 2021; 7:618256. [PMID: 33553213 PMCID: PMC7859274 DOI: 10.3389/fmed.2020.618256] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/30/2020] [Indexed: 12/26/2022] Open
Abstract
Solute Carrier Family 26 (SLC26) is a conserved anion transporter family with 10 members in human (SLC26A1-A11, A10 being a pseudogene). All SLC26 genes except for SLC26A5 (prestin) are versatile anion exchangers with notable ability to transport a variety of anions. SLC26A6 has the most extensive exchange functions in the SLC26 family and is widely expressed in various organs and tissues of mammals. SLC26A6 has some special properties that make it play a particularly important role in ion homeostasis and acid-base balance. In the past few years, the function of SLC26A6 in the diseases has received increasing attention. SLC26A6 not only participates in the development of intestinal and pancreatic diseases but also serves a significant role in mediating nephrolithiasis, fetal skeletal dysplasia and arrhythmia. This review aims to explore the role of SLC26A6 in physiology and pathophysiology of relative mammalian organs to guide in-depth studies about related diseases of human.
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Affiliation(s)
- Juan Wang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Wenkang Wang
- Department of Critical Care Medicine of the Third Affiliated Hospital (The First People's Hospital of Zunyi City), Zunyi Medical University, Zunyi, China
| | - Hui Wang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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24
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Moss FJ, Boron WF. Carbonic anhydrases enhance activity of endogenous Na-H exchangers and not the electrogenic Na/HCO 3 cotransporter NBCe1-A, expressed in Xenopus oocytes. J Physiol 2020; 598:5821-5856. [PMID: 32969493 PMCID: PMC7747792 DOI: 10.1113/jp280143] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/07/2020] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS According to the HCO 3 - metabolon hypothesis, direct association of cytosolic carbonic anhydrases (CAs) with the electrogenic Na/HCO3 cotransporter NBCe1-A speeds transport by regenerating/consuming HCO 3 - . The present work addresses published discrepancies as to whether cytosolic CAs stimulate NBCe1-A, heterologously expressed in Xenopus oocytes. We confirm the essential elements of the previous experimental observations, taken as support for the HCO 3 - metabolon hypothesis. However, using our own experimental protocols or those of others, we find that NBCe1-A function is unaffected by cytosolic CAs. Previous conclusions that cytosolic CAs do stimulate NBCe1-A can be explained by an unanticipated stimulatory effect of the CAs on an endogenous Na-H exchanger. Theoretical analyses show that, although CAs could stimulate non- HCO 3 - transporters (e.g. Na-H exchangers) by accelerating CO2 / HCO 3 - -mediated buffering of acid-base equivalents, they could not appreciably affect transport rates of NBCe1 or other transporters carrying HCO 3 - , CO 3 = , or NaCO 3 - ion pairs. ABSTRACT The HCO 3 - metabolon hypothesis predicts that cytosolic carbonic anhydrase (CA) binds to NBCe1-A, promotes HCO 3 - replenishment/consumption, and enhances transport. Using a short step-duration current-voltage (I-V) protocol with Xenopus oocytes expressing eGFP-tagged NBCe1-A, our group reported that neither injecting human CA II (hCA II) nor fusing hCA II to the NBCe1-A carboxy terminus affects background-subtracted NBCe1 slope conductance (GNBC ), which is a direct measure of NBCe1-A activity. Others - using bovine CA (bCA), untagged NBCe1-A, and protocols keeping holding potential (Vh ) far from NBCe1-A's reversal potential (Erev ) for prolonged periods - found that bCA increases total membrane current (ΔIm ), which apparently supports the metabolon hypothesis. We systematically investigated differences in the two protocols. In oocytes expressing untagged NBCe1-A, injected with bCA and clamped to -40 mV, CO2 / HCO 3 - exposures markedly decrease Erev , producing large transient outward currents persisting for >10 min and rapid increases in [Na+ ]i . Although the CA inhibitor ethoxzolamide (EZA) reduces both ΔIm and d[Na+ ]i /dt, it does not reduce GNBC . In oocytes not expressing NBCe1-A, CO2 / HCO 3 - triggers rapid increases in [Na+ ]i that both hCA II and bCA enhance in concentration-dependent manners. These d[Na+ ]i /dt increases are inhibited by EZA and blocked by EIPA, a Na-H exchanger (NHE) inhibitor. In oocytes expressing untagged NBCe1-A and injected with bCA, EIPA abolishes the EZA-dependent decreases in ΔIm and d[Na+ ]i /dt. Thus, CAs/EZA produce their ΔIm and d[Na+ ]i /dt effects not through NBCe1-A, but endogenous NHEs. Theoretical considerations argue against a CA stimulation of HCO 3 - transport, supporting the conclusion that an NBCe1-A- HCO 3 - metabolon does not exist in oocytes.
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Affiliation(s)
- Fraser J. Moss
- Department of Physiology and Biophysics, Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Walter F. Boron
- Department of Physiology and Biophysics, Western Reserve University School of Medicine, Cleveland, OH 44106, USA
- Department of Medicine and Department of Biochemistry Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
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25
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Intracellular Ca 2+-Mediated AE2 Is Involved in the Vectorial Movement of HaCaT Keratinocyte. Int J Mol Sci 2020; 21:ijms21228429. [PMID: 33182643 PMCID: PMC7698169 DOI: 10.3390/ijms21228429] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/19/2022] Open
Abstract
Keratinocyte migration is initiated toward the wound skin barrier as a crucial process in wound healing. However, the migratory machinery used by keratinocytes is relatively unknown. Histamine signaling, including an increase in the Ca2+ signal, mediated the enhanced protein expression and chloride/bicarbonate exchange activity of anion exchanger AE2 in keratinocytes. In this study, we applied an agarose spot assay to induce a vectorial motion. The vectorial stimulation of the histamine-containing agarose spot enhanced the HaCaT keratinocyte migration, compared to non-directional stimulation. AE2 is associated with the vectorial movement of HaCaT keratinocytes. Enhanced expression of AE2 was mainly associated with an increase in Ca2+ and was abolished by the treatment with the Ca2+ chelating agent BAPTA-AM. These findings revealed that the directionality of Ca2+-exerted stimulation can play a prominent role in facilitating migration through the involvement of AE2 as a migratory machinery in HaCaT keratinocytes.
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26
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Slc4 Gene Family in Spotted Sea Bass (Lateolabrax maculatus): Structure, Evolution, and Expression Profiling in Response to Alkalinity Stress and Salinity Changes. Genes (Basel) 2020; 11:genes11111271. [PMID: 33126655 PMCID: PMC7692064 DOI: 10.3390/genes11111271] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 10/23/2020] [Accepted: 10/26/2020] [Indexed: 12/11/2022] Open
Abstract
The solute carrier 4 (SLC4) family is a class of cell membranes transporters involved in base transport that plays crucial roles in diverse physiological processes. In our study, 15 slc4 genes were identified and annotated in spotted sea bass, including five members of Cl−/HCO3− exchangers, eight genes coding Na+-dependent HCO3− transporters, and two copies of Na+-coupled borate transporters. The gene sequence and structure, chromosomal and syntenic arrangement, phylogenetic and evolution profiles were analyzed. Results showed that the slc4 gene in teleosts obviously expanded compared with higher vertebrates, arising from teleost-specific whole genome duplication event. Most gene sites of slc4 in spotted sea bass were under strong purifying selection during evolution, while positive selection sites were only detected in slc4a1b, slc4a8, and slc4a10b. Additionally, qRT-PCR results showed that different slc4 genes exhibited distinct branchial expression patterns after alkalinity and salinity stresses, of which the strongly responsive members may play essential roles during these physiological processes. Our study provides the systemic overview of the slc4 gene family in spotted sea bass and enables a better understanding for the evolution of this family and further deciphering the biological roles in maintaining ion and acid–base homeostasis in teleosts.
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27
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Blanco-Ameijeiras S, Stoll HM, Zhang H, Hopkinson BM. Influence of Temperature and CO 2 On Plasma-membrane Permeability to CO 2 and HCO 3- in the Marine Haptophytes Emiliania huxleyi and Calcidiscus leptoporus (Prymnesiophyceae). JOURNAL OF PHYCOLOGY 2020; 56:1283-1294. [PMID: 32418211 DOI: 10.1111/jpy.13017] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/28/2020] [Indexed: 06/11/2023]
Abstract
Membrane permeabilities to CO2 and HCO3- constrain the function of CO2 concentrating mechanisms that algae use to supply inorganic carbon for photosynthesis. In diatoms and green algae, plasma membranes are moderately to highly permeable to CO2 but effectively impermeable to HCO3- . Here, CO2 and HCO3- membrane permeabilities were measured using an 18 O-exchange technique on two species of haptophyte algae, Emiliania huxleyi and Calcidiscus leptoporus, which showed that the plasma membranes of these species are also highly permeable to CO2 (0.006-0.02 cm · s-1 ) but minimally permeable to HCO3- . Increased temperature and CO2 generally increased CO2 membrane permeabilities in both species, possibly due to changes in lipid composition or CO2 channel proteins. Changes in CO2 membrane permeabilities showed no association with the density of calcium carbonate coccoliths surrounding the cell, which could potentially impede passage of compounds. Haptophyte plasma-membrane permeabilities to CO2 were somewhat lower than those of diatoms but generally higher than membrane permeabilities of green algae. One caveat of these measurements is that the model used to interpret 18 O-exchange data assumes that carbonic anhydrase, which catalyzes 18 O-exchange, is homogeneously distributed in the cell. The implications of this assumption were tested using a two-compartment model with an inhomogeneous distribution of carbonic anhydrase to simulate 18 O-exchange data and then inferring plasma-membrane CO2 permeabilities from the simulated data. This analysis showed that the inferred plasma-membrane CO2 permeabilities are minimal estimates but should be quite accurate under most conditions.
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Affiliation(s)
| | - Heather M Stoll
- Department of Earth Sciences, ETH Zurich, Sonnegstrasse 5, Zurich, 8092, Switzerland
| | - Hongrui Zhang
- Department of Earth Sciences, ETH Zurich, Sonnegstrasse 5, Zurich, 8092, Switzerland
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Brian M Hopkinson
- Department of Marine Sciences, University of Georgia, Athens, Georgia, 30602, USA
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Karolak JA, Ginter-Matuszewska B, Tomela K, Kabza M, Nowak-Malczewska DM, Rydzanicz M, Polakowski P, Szaflik JP, Gajecka M. Further evaluation of differential expression of keratoconus candidate genes in human corneas. PeerJ 2020; 8:e9793. [PMID: 32879808 PMCID: PMC7443321 DOI: 10.7717/peerj.9793] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/31/2020] [Indexed: 12/26/2022] Open
Abstract
Background Keratoconus (KTCN) is a progressive eye disease, characterized by changes in the shape and thickness of the cornea that results in loss of visual acuity. While numerous KTCN candidate genes have been identified, the genetic etiology of the disease remains undetermined. To further investigate and verify the contribution of particular genetic factors to KTCN, we assessed 45 candidate genes previously indicated as involved in KTCN etiology based on transcriptomic and genomic data. Methods The RealTime ready Custom Panel, covering 45 KTCN candidate genes and two reference transcripts, has been designed. Then, the expression profiles have been assessed using the RT-qPCR assay in six KTCN and six non-KTCN human corneas, obtained from individuals undergoing a penetrating keratoplasty procedure. Results In total, 35 genes exhibiting differential expression between KTCN and non-KTCN corneas have been identified. Among these genes were ones linked to the extracellular matrix formation, including collagen synthesis or the TGF-β, Hippo, and Wnt signaling pathways. The most downregulated transcripts in KTCN corneas were CTGF, TGFB3, ZNF469, COL5A2, SMAD7, and SPARC, while TGFBI and SLC4A11 were the most upregulated ones. Hierarchical clustering of expression profiles demonstrated almost clear separation between KTCN and non-KTCN corneas. The gene expression levels determined using RT-qPCR showed a strong correlation with previous RNA sequencing (RNA-Seq) results. Conclusions A strong correlation between RT-qPCR and earlier RNA-Seq data confirms the possible involvement of genes from collagen synthesis and the TGF-β, Hippo, and Wnt signaling pathways in KTCN etiology. Our data also revealed altered expression of several genes, such as LOX, SPARC, and ZNF469, in which single nucleotide variants have been frequently identified in KTCN. These findings further highlight the heterogeneous nature of KTCN.
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Affiliation(s)
- Justyna A Karolak
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Poznan, Poland.,Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | - Barbara Ginter-Matuszewska
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Poznan, Poland
| | - Katarzyna Tomela
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Poznan, Poland.,Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
| | - Michal Kabza
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Poznan, Poland
| | - Dorota M Nowak-Malczewska
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Poznan, Poland
| | | | - Piotr Polakowski
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Jacek P Szaflik
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Marzena Gajecka
- Chair and Department of Genetics and Pharmaceutical Microbiology, Poznan University of Medical Sciences, Poznan, Poland.,Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland
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29
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Zhang M, Li T, Zhu J, Tuo B, Liu X. Physiological and pathophysiological role of ion channels and transporters in the colorectum and colorectal cancer. J Cell Mol Med 2020; 24:9486-9494. [PMID: 32662230 PMCID: PMC7520301 DOI: 10.1111/jcmm.15600] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/16/2020] [Accepted: 06/18/2020] [Indexed: 12/24/2022] Open
Abstract
The incidence of colorectal cancer has increased annually, and the pathogenesis of this disease requires further investigation. In normal colorectal tissues, ion channels and transporters maintain the water‐electrolyte balance and acid/base homeostasis. However, dysfunction of these ion channels and transporters leads to the development and progression of colorectal cancer. Therefore, this review focuses on the progress in understanding the roles of ion channels and transporters in the colorectum and in colorectal cancer, including aquaporins (AQPs), Cl− channels, Cl−/HCO3‐ exchangers, Na+/HCO3‐ transporters and Na+/H+ exchangers. The goal of this review is to promote the identification of new targets for the treatment and prognosis of colorectal cancer.
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Affiliation(s)
- Minglin Zhang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Taolang Li
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Jiaxing Zhu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Xuemei Liu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
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30
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Human Sperm Capacitation Involves the Regulation of the Tyr-Phosphorylation Level of the Anion Exchanger 1 (AE1). Int J Mol Sci 2020; 21:ijms21114063. [PMID: 32517126 PMCID: PMC7311965 DOI: 10.3390/ijms21114063] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 12/22/2022] Open
Abstract
Bicarbonate uptake is one of the early steps of capacitation, but the identification of proteins regulating anion fluxes remains elusive. The aim of this study is to investigate the role of sperm solute carrier 4 (SLC4) A1 (spAE1) in the capacitation process. The expression, location, and tyrosine-phosphorylation (Tyr-P) level of spAE1 were assessed. Thereby, it was found that 4,4′-Diisothiocyano-2,2′-stilbenedisulfonic acid (DIDS), an SLC4 family channel blocker, inhibited capacitation in a dose-dependent manner by decreasing acrosome reaction (ARC% 24.5 ± 3.3 vs. 64.9 ± 4.3, p < 0.05) and increasing the percentage of not viable cells (NVC%), comparable to the inhibition by I-172, a cystic fibrosis transmembrane conductance regulator (CFTR) blocker (AR% 30.5 ± 4.4 and NVC% 18.6 ± 2.2). When used in combination, a synergistic inhibitory effect was observed with a remarkable increase of the percentage of NVC (45.3 ± 4.1, p < 0.001). spAE1 was identified in sperm membrane as a substrate for Tyr-protein kinases Lyn and Syk, which were identified as both soluble and membrane-bound pools. spAE1-Tyr-P level increased in the apical region of sperm under capacitating conditions and was negatively affected by I-172 or DIDS, and, to a far greater extent, by a combination of both. In conclusion, we demonstrated that spAE1 is expressed in sperm membranes and it is phosphorylated by Syk, but above all by Lyn on Tyr359, which are involved in sperm viability and capacitation.
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Abstract
Although students initially learn of ionic buffering in basic chemistry, buffering and acid-base transport in biology often is relegated to specialized classes, discussions, or situations. That said, for physiology, nephrology, pulmonology, and anesthesiology, these basic principles often are critically important for mechanistic understanding, medical treatments, and assessing therapy effectiveness. This short introductory perspective focuses on basic chemistry and transport of buffers and acid-base equivalents, provides an outline of basic science acid-base concepts, tools used to monitor intracellular pH, model cellular responses to pH buffer changes, and the more recent development and use of genetically encoded pH-indicators. Examples of newer genetically encoded pH-indicators (pHerry and pHire) are provided, and their use for in vitro, ex vivo, and in vivo experiments are described. The continued use and development of these basic tools provide increasing opportunities for both basic and potentially clinical investigations.
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Affiliation(s)
- Michael F Romero
- Physiology and Biomedical Engineering, Nephrology and Hypertension, Mayo Clinic College of Medicine and Science, Rochester, MN.
| | - Adam J Rossano
- Physiology and Biomedical Engineering, Nephrology and Hypertension, Mayo Clinic College of Medicine and Science, Rochester, MN
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32
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Abstract
Maintenance of the main Golgi functions, glycosylation and sorting, is dependent on the unique Golgi pH microenvironment that is thought to be set by the balance between the rates of V-ATPase-mediated proton pumping and its leakage back to the cytoplasm via an unknown pathway. The concentration of other ions, such as chloride, potassium, calcium, magnesium, and manganese, is also important for Golgi homeostasis and dependent on the transport activity of other ion transporters present in the Golgi membranes. During the last decade, several new disorders have been identified that are caused by, or are associated with, dysregulated Golgi pH and ion homeostasis. Here, we will provide an updated overview on these disorders and the proteins involved. We will also discuss other disorders for which the molecular defects remain currently uncertain but which potentially involve proteins that regulate Golgi pH or ion homeostasis.
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Dai GP, Wang LP, Wen YQ, Ren XQ, Zuo SG. Identification of key genes for predicting colorectal cancer prognosis by integrated bioinformatics analysis. Oncol Lett 2019; 19:388-398. [PMID: 31897151 PMCID: PMC6924121 DOI: 10.3892/ol.2019.11068] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 09/17/2019] [Indexed: 12/24/2022] Open
Abstract
Colorectal cancer (CRC) is a life-threatening disease with a poor prognosis. Therefore, it is crucial to identify molecular prognostic biomarkers for CRC. The present study aimed to identify potential key genes that could be used to predict the prognosis of patients with CRC. Three CRC microarray datasets (GSE20916, GSE73360 and GSE44861) were downloaded from the Gene Expression Omnibus (GEO) database, and one dataset was obtained from The Cancer Genome Atlas (TCGA) database. The three GEO datasets were analyzed to detect differentially expressed genes (DEGs) using the BRB-ArrayTools software. Functional and pathway enrichment analyses of these DEGs were performed using the Database for Annotation, Visualization and Integrated Discovery tool. A protein-protein interaction (PPI) network of DEGs was constructed, hub genes were extracted, and modules of the PPI network were analyzed. To investigate the prognostic values of the hub genes in CRC, data from the CRC datasets of TCGA were used to perform the survival analyses based on the sample splitting method and Cox regression model. Correlation among the hub genes was evaluated using Spearman's correlation analysis. In the three GEO datasets, a total of 105 common DEGs were identified, including 51 down- and 54 up-regulated genes in CRC compared with normal colorectal tissues. A PPI network consisting of 100 DEGs and 551 edges was constructed, and 44 nodes were identified as hub genes. Among these 44 genes, the four hub genes TIMP metallopeptidase inhibitor 1 (TIMP1), solute carrier family 4 member 4 (SLC4A4), aldo-keto reductase family 1 member B10 (AKR1B10) and ATP binding cassette subfamily E member 1 (ABCE1) were associated with overall survival (OS) in patients with CRC. Three significant modules were extracted from the PPI network. The hub gene TIMP1 was present in Module 1, ABCE1 was involved in Module 2 and SLC4A4 was identified in Module 3. Univariate analysis revealed that TIMP1, SLC4A4, AKR1B10 and ABCE1 were associated with the OS of patients with CRC. Multivariate analysis demonstrated that SLC4A4 may be an independent prognostic factor associated with OS. Furthermore, the results from correlation analysis revealed that there was no correlation between TIMP1, SLC4A4 and ABCE1, whereas AKR1B10 was positively correlated with SLC4A4. In conclusion, the four key genes TIMP1, SLC4A4, AKR1B10 and ABCE1 associated with the OS of patients with CRC were identified by integrated bioinformatics analysis. These key genes may be used as prognostic biomarkers to predict the survival of patients with CRC, and may therefore represent novel therapeutic targets for CRC.
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Affiliation(s)
- Gong-Peng Dai
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475001, P.R. China
| | - Li-Ping Wang
- Center for Translational Medicine, Huaihe Hospital of Henan University, Kaifeng, Henan 475001, P.R. China
| | - Yu-Qing Wen
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475001, P.R. China
| | - Xue-Qun Ren
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475001, P.R. China
| | - Shu-Guang Zuo
- Center for Translational Medicine, Huaihe Hospital of Henan University, Kaifeng, Henan 475001, P.R. China.,Institute of Infection and Immunity, Huaihe Hospital of Henan University, Kaifeng, Henan 475001, P.R. China
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Racz R, Nagy A, Rakonczay Z, Dunavari EK, Gerber G, Varga G. Defense Mechanisms Against Acid Exposure by Dental Enamel Formation, Saliva and Pancreatic Juice Production. Curr Pharm Des 2019; 24:2012-2022. [PMID: 29769002 PMCID: PMC6225347 DOI: 10.2174/1381612824666180515125654] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 04/30/2018] [Accepted: 05/08/2018] [Indexed: 12/16/2022]
Abstract
The pancreas, the salivary glands and the dental enamel producing ameloblasts have marked developmental, structural and functional similarities. One of the most striking similarities is their bicarbonate-rich secretory product, serving acid neutralization. An important difference between them is that while pancreatic juice and saliva are delivered into a lumen where they can be collected and analyzed, ameloblasts produce locally precipitating hydroxyapatite which cannot be easily studied. Interestingly, the ion and protein secretion by the pancreas, the salivary glands, and maturation ameloblasts are all two-step processes, of course with significant differences too. As they all have to defend against acid exposure by producing extremely large quantities of bicarbonate, the failure of this function leads to deteriorating consequences. The aim of the present review is to describe and characterize the defense mechanisms of the pancreas, the salivary glands and enamel-producing ameloblasts against acid exposure and to compare their functional capabilities to do this by producing bicarbonate.
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Affiliation(s)
- Robert Racz
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Akos Nagy
- Department of Dentistry, Oral and Maxillofacial Surgery, University of Pecs, Pecs, Hungary
| | - Zoltan Rakonczay
- Department of Pathophysiology, University of Szeged, Szeged, Hungary
| | - Erika Katalin Dunavari
- Department of Dentistry, Oral and Maxillofacial Surgery, University of Pecs, Pecs, Hungary
| | - Gabor Gerber
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - Gabor Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
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35
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Ma Z, Yuan D, Cheng X, Tuo B, Liu X, Li T. Function of ion transporters in maintaining acid-base homeostasis of the mammary gland and the pathophysiological role in breast cancer. Am J Physiol Regul Integr Comp Physiol 2019; 318:R98-R111. [PMID: 31553634 DOI: 10.1152/ajpregu.00202.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The incidence of breast cancer is increasing year by year, and the pathogenesis is still unclear. Studies have shown that the high metabolism of solid tumors leads to an increase in hypoxia, glycolysis, production of lactic acid and carbonic acid, and extracellular acidification; a harsh microenvironment; and ultimately to tumor cell death. Approximately 50% of locally advanced breast cancers exhibit hypoxia and/or local hypoxia, and acid-base regulatory proteins play an important role in regulating milk secretion and maintaining mammary gland physiological function. Therefore, ion transporters have gradually become a hot topic in mammary gland and breast cancer research. This review focuses on the research progress of ion transporters in mammary glands and breast cancer. We hope to provide new targets for the treatment and prognosis of breast cancer.
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Affiliation(s)
- Zhiyuan Ma
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Dumin Yuan
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Xiaoming Cheng
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Xuemei Liu
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, China.,Digestive Disease Institute of Guizhou Province, Zunyi, China
| | - Taolang Li
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, China
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36
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Kellokumpu S. Golgi pH, Ion and Redox Homeostasis: How Much Do They Really Matter? Front Cell Dev Biol 2019; 7:93. [PMID: 31263697 PMCID: PMC6584808 DOI: 10.3389/fcell.2019.00093] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 05/16/2019] [Indexed: 02/06/2023] Open
Abstract
Exocytic and endocytic compartments each have their own unique luminal ion and pH environment that is important for their normal functioning. A failure to maintain this environment - the loss of homeostasis - is not uncommon. In the worst case, all the main Golgi functions, including glycosylation, membrane trafficking and protein sorting, can be perturbed. Several factors contribute to Golgi homeostasis. These include not only ions such as H+, Ca2+, Mg2+, Mn2+, but also Golgi redox state and nitric oxide (NO) levels, both of which are dependent on the oxygen levels in the cells. Changes to any one of these factors have consequences on Golgi functions, the nature of which can be dissimilar or similar depending upon the defects themselves. For example, altered Golgi pH homeostasis gives rise to Cutis laxa disease, in which glycosylation and membrane trafficking are both affected, while altered Ca2+ homeostasis due to the mutated SCPA1 gene in Hailey-Hailey disease, perturbs various protein sorting, proteolytic cleavage and membrane trafficking events in the Golgi. This review gives an overview of the molecular machineries involved in the maintenance of Golgi ion, pH and redox homeostasis, followed by a discussion of the organelle dysfunction and disease that frequently result from their breakdown. Congenital disorders of glycosylation (CDGs) are discussed only when they contribute directly to Golgi pH, ion or redox homeostasis. Current evidence emphasizes that, rather than being mere supporting factors, Golgi pH, ion and redox homeostasis are in fact key players that orchestrate and maintain all Golgi functions.
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Affiliation(s)
- Sakari Kellokumpu
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
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37
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Begum S, Ahmed N, Mubarak M, Mateen SM, Khalid N, Rizvi SAH. Modulation of Renal Parenchyma in Response to Allogeneic Adipose-Derived Mesenchymal Stem Cells Transplantation in Acute Kidney Injury. Int J Stem Cells 2019; 12:125-138. [PMID: 30836723 PMCID: PMC6457705 DOI: 10.15283/ijsc18091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Revised: 12/29/2018] [Accepted: 01/08/2019] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND AND OBJECTIVES In regenerative medicine, mesenchymal stem cells derived from adipose tissues (Ad-MSCs) are a very attractive target to treat many diseases. In relation to nephrology, the aim of the current study is to investigate the effects of Ad-MSCs for the amelioration of acute kidney injury and to explore the mechanism of renal parenchymal changes in response to allogeneic transplantation of Ad-MSCs. METHODS AND RESULTS The nephrotoxicity was induced by cisplatin (CP) in balb/c mice according to RIFLE Class and AKIN Stage 3. PCR, qRT-PCR and fluorescent labeled cells infusion, histopathology, immunohistochemistry, functional analyses were used for genes and proteins expressions data acquisition respectively. We demonstrated that single intravenous infusion of 2.5×107/kg mAd-MSCs in mice pre-injected with CP recruited to the kidney, restored the renal structure, and function, which resulted in progressive survival of mice. The renal tissue morphology was recovered in terms of diminished necrosis or epithelial cells damage, protein casts formation, infiltration of inflammatory cells, tubular dilatation, and restoration of brush border protein; Megalin and decreased Kim-1 expressions in mAd-MSCs transplanted mice. Significant reduction in serum creatinine with slashed urea and urinary protein levels were observed. Anti-BrdU staining displayed enhanced tubular cells proliferation. Predominantly, downgrade expressions of TNF-α and TGF-β1 were observed post seven days in mAd-MSCs transplanted mice. CONCLUSIONS Ad-MSCs exerts pro-proliferative, anti-inflammatory, and anti-fibrotic effects. Ad-MSCs transplantation without any chemical or genetic manipulation can provide the evidence of therapeutic strategy for the origin of regeneration and overall an improved survival of the system in functionally deprived failed kidneys.
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Affiliation(s)
- Sumreen Begum
- Stem Cells Research Laboratory (SCRL), Karachi,
Pakistan
| | - Nazia Ahmed
- Stem Cells Research Laboratory (SCRL), Karachi,
Pakistan
| | | | | | - Nida Khalid
- Stem Cells Research Laboratory (SCRL), Karachi,
Pakistan
| | - Syed Adibul Hasan Rizvi
- Department of Urology, Sindh Institute of Urology and Transplantation (SIUT), Karachi,
Pakistan
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38
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Jaunet-Lahary T, Vercauteren DP, Fleury F, Laurent AD. Computational simulations determining disulfonic stilbene derivative bioavailability within human serum albumin. Phys Chem Chem Phys 2019; 20:18020-18030. [PMID: 29931001 DOI: 10.1039/c8cp00704g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Disulfonic stilbene (DS) derivatives are a member of the large family of compounds widely employed in medicine and biology as modulators for membrane transporters or inhibitors of a protein involved in DNA repair. They constitute interesting compounds that have not yet been investigated within the bioavailability framework. No crystallographic structures exist involving such compounds embedded in the most common drug carrier, human serum albumin (HSA). The present work studies, for the first time, the physico-chemical features driving the inclusion of three DS derivatives (amino, nitro and acetamido, named DADS, DNDS and DATDS, respectively) within the four common HSA binding sites using combined molecular docking and molecular dynamics simulations. A careful analysis of each ligand within each of the studied binding sites is carried out, highlighting specific interactions and key residues playing a role in stabilizing the ligand within each pocket. The comparison between DADS, DNDS and DATDS reveals that depending on the binding site, the conclusions are rather different. For instance, the IB binding site shows a specificity to DADS compounds while IIIA is the most favorable site for DNDS and DATDS.
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Affiliation(s)
- Titouan Jaunet-Lahary
- Laboratoire CEISAM - UMR CNRS 6230, Université de Nantes, 2 Rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France.
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Lema SC, Carvalho PG, Egelston JN, Kelly JT, McCormick SD. Dynamics of Gene Expression Responses for Ion Transport Proteins and Aquaporins in the Gill of a Euryhaline Pupfish during Freshwater and High-Salinity Acclimation. Physiol Biochem Zool 2019; 91:1148-1171. [PMID: 30334669 DOI: 10.1086/700432] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Pupfishes (genus Cyprinodon) evolved some of the broadest salinity tolerances of teleost fishes, with some taxa surviving in conditions from freshwater to nearly 160 ppt. In this study, we examined transcriptional dynamics of ion transporters and aquaporins in the gill of the desert Amargosa pupfish (Cyprinodon nevadensis amargosae) during rapid salinity change. Pupfish acclimated to 7.5 ppt were exposed to freshwater (0.3 ppt), seawater (35 ppt), or hypersaline (55 ppt) conditions over 4 h and sampled at these salinities over 14 d. Plasma osmolality and Cl- concentration became elevated 8 h after the start of exposure to 35 or 55 ppt but returned to baseline levels after 14 d. Osmolality recovery was paralleled by increased gill Na+/K+-ATPase activity and higher relative levels of messenger RNAs (mRNAs) encoding cystic fibrosis transmembrane conductance regulator (cftr) and Na+/K+/2Cl- cotransporter-1 (nkcc1). Transcripts encoding one Na+-HCO3- cotransporter-1 isoform (nbce1.1) also increased in the gills at higher salinities, while a second isoform (nbce1.2) increased expression in freshwater. Pupfish in freshwater also had lower osmolality and elevated gill mRNAs for Na+/H+ exchanger isoform-2a (nhe2a) and V-type H+-ATPase within 8 h, followed by increases in Na+/H+ exchanger-3 (nhe3), carbonic anhydrase 2 (ca2), and aquaporin-3 (aqp3) within 1 d. Gill mRNAs for Na+/Cl- cotransporter-2 (ncc2) also were elevated 14 d after exposure to 0.3 ppt. These results offer insights into how coordinated transcriptional responses for ion transporters in the gill facilitate reestablishment of osmotic homeostasis after changes in environmental salinity and provide evidence that the teleost gill expresses two Na+-HCO3- cotransporter-1 isoforms with different roles in freshwater and seawater acclimation.
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Brauner CJ, Shartau RB, Damsgaard C, Esbaugh AJ, Wilson RW, Grosell M. Acid-base physiology and CO2 homeostasis: Regulation and compensation in response to elevated environmental CO2. FISH PHYSIOLOGY 2019. [DOI: 10.1016/bs.fp.2019.08.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Reality of Inhibitory GABA in Neonatal Brain: Time to Rewrite the Textbooks? J Neurosci 2018; 36:10242-10244. [PMID: 27707962 DOI: 10.1523/jneurosci.2270-16.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 08/26/2016] [Indexed: 12/30/2022] Open
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42
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Hu MY, Yan JJ, Petersen I, Himmerkus N, Bleich M, Stumpp M. A SLC4 family bicarbonate transporter is critical for intracellular pH regulation and biomineralization in sea urchin embryos. eLife 2018; 7:36600. [PMID: 29714685 PMCID: PMC5986267 DOI: 10.7554/elife.36600] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 04/30/2018] [Indexed: 12/21/2022] Open
Abstract
Efficient pH regulation is a fundamental requisite of all calcifying systems in animals and plants but with the underlying pH regulatory mechanisms remaining largely unknown. Using the sea urchin larva, this work identified the SLC4 HCO3- transporter family member SpSlc4a10 to be critically involved in the formation of an elaborate calcitic endoskeleton. SpSlc4a10 is specifically expressed by calcifying primary mesenchyme cells with peak expression during de novo formation of the skeleton. Knock-down of SpSlc4a10 led to pH regulatory defects accompanied by decreased calcification rates and skeleton deformations. Reductions in seawater pH, resembling ocean acidification scenarios, led to an increase in SpSlc4a10 expression suggesting a compensatory mechanism in place to maintain calcification rates. We propose a first pH regulatory and HCO3- concentrating mechanism that is fundamentally linked to the biological precipitation of CaCO3. This knowledge will help understanding biomineralization strategies in animals and their interaction with a changing environment. Many marine organisms such as mussels, sea urchins or corals, have skeletons and shells, which – due to their beautiful colors and shapes – are often desirable collector pieces. These structures are made from calcium and carbonate ions that react to form calcium carbonate crystals in a process known as biomineralization. In sea urchin larvae, for example, the skeleton is built by so-called primary mesenchyme cells, which work similar to the bone forming cells in mammals. These mesenchyme cells use calcium from the sea water, which travels to the site where the shell starts to form. About half of the carbonate comes from carbon dioxide that the animals make as they breathe, but it is not known how the other half gets to the site of biomineralization. Producing a skeleton generates acid, and marine animals need to be able to regulate their pH levels, as too acidic environments can dissolve the calcium carbonate and threatening to destroy the developing shell. How cells accumulate enough carbonate to make their shells, and how they cope with acidity is still poorly understood. Here, Hu et al. address this problem by studying purple sea urchin larvae, revealing that they use ion transporters to gather bicarbonate from seawater. These structures are part of a group of bicarbonate transporters known as the ‘SLC4 transporter family’, which sit across the membrane of the mesenchyme cells and move the bicarbonate ions along. As the sea urchin larvae develop, the levels of the transporter protein start to rise in mesenchyme cells, peaking around the time they are producing the skeleton. Stopping the production of the transporter hindered the larvae from building normal skeletons and also made their cells more acidic. It turns out that bicarbonate is more than a skeleton ingredient – it also helps to buffer the acid made in the process. Bicarbonate ions can combine with acidic molecules to form water and carbon dioxide. Bicarbonate pumped in from the sea neutralises the acidic molecules made during calcium carbonate formation, which helps to stabilize pH levels. When the acidity of the water was experimentally increased, it prompted the sea urchins to produce more of the SLC4 transporters, revealing that they may have another role to play. Their acid-neutralizing capability helped the animals to cope with changes in their environment. Taking on more bicarbonate could therefore help to compensate for rising acidity, allowing skeleton production to carry on as normal. This last finding is important in the context of ocean acidification. As the amount of carbon dioxide in the atmosphere increases, more of the gas dissolves in the sea. The chemical reactions that follow make the water more acidic and decreases the pH levels of the sea. Understanding how animals make their skeletons and shells, and manage acid, could reveal how they will cope as the environment changes in the future.
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Affiliation(s)
- Marian Y Hu
- Institute of Physiology, Christian-Albrechts University of Kiel, Kiel, Germany
| | - Jia-Jiun Yan
- Institute of Physiology, Christian-Albrechts University of Kiel, Kiel, Germany.,Institute of Cellular and Organismic Biology, Taipei, Taiwan
| | - Inga Petersen
- Institute of Physiology, Christian-Albrechts University of Kiel, Kiel, Germany
| | - Nina Himmerkus
- Institute of Physiology, Christian-Albrechts University of Kiel, Kiel, Germany
| | - Markus Bleich
- Institute of Physiology, Christian-Albrechts University of Kiel, Kiel, Germany
| | - Meike Stumpp
- Comparative Immunobiology, Institute of Zoology, Christian-Albrechts University of Kiel, Kiel, Germany
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43
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Caushi D, Martens H. Absorption of bicarbonate in sheep omasum. Res Vet Sci 2018; 118:324-330. [PMID: 29601970 DOI: 10.1016/j.rvsc.2018.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 03/07/2018] [Accepted: 03/09/2018] [Indexed: 10/17/2022]
Abstract
Transport of bicarbonate across the isolated epithelium of sheep omasum was studied in vitro in Ussing chambers in combination with the pH-Stat method. The transport of HCO3- occurred in both directions, but Jms HCO3- was significant larger than Jsm. Reducing the activity of the apical Na/H exchanger by a low mucosal Na concentration caused a significant reduction of Jms HCO3-. Mucosal amiloride or short chain fatty acids (25 mmol l-1 SCFA) numerically decreased Jms HCO3-, but their combination (amiloride + SCFA) caused a significant reduction, which was also observed after addition of the carboanhydrase inhibitor ethoxyzolamide. Concentrations of 5 or 15 mmol·l-1 mucosal ammonia did not change transport rates. The obtained results indicate the importance of an undisturbed cytosolic pH for transcellular HCO3- transport, which is probably mediated by an anion exchanger in both the apical and basolateral membranes. Possible impairment of HCO3- transport appears to be an overlooked factor in the pathogenesis of displacement of the abomasum.
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Affiliation(s)
- Driton Caushi
- Freie Universitaet Berlin, Department of Veterinary Physiology, Oertzenweg 19b, 14163 Berlin, Germany.
| | - Holger Martens
- Freie Universitaet Berlin, Department of Veterinary Physiology, Oertzenweg 19b, 14163 Berlin, Germany.
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44
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Chen GS, Lee SP, Huang SF, Chao SC, Chang CY, Wu GJ, Li CH, Loh SH. Functional and molecular characterization of transmembrane intracellular pH regulators in human dental pulp stem cells. Arch Oral Biol 2018. [PMID: 29524788 DOI: 10.1016/j.archoralbio.2018.02.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Homeostasis of intracellular pH (pHi) plays vital roles in many cell functions, such as proliferation, apoptosis, differentiation and metastasis. Thus far, Na+-H+ exchanger (NHE), Na+-HCO3- co-transporter (NBC), Cl-/HCO3- exchanger (AE) and Cl-/OH- exchanger (CHE) have been identified to co-regulate pHi homeostasis. However, functional and biological pHi-regulators in human dental pulp stem cells (hDPSCs) have yet to be identified. DESIGN Microspectrofluorimetry technique with pH-sensitive fluorescent dye, BCECF, was used to detect pHi changes. NH4Cl and Na+-acetate pre-pulse were used to induce intracellular acidosis and alkalosis, respectively. Isoforms of pHi-regulators were detected by Western blot technique. RESULTS The resting pHi was no significant difference between that in HEPES-buffered (nominal HCO3--free) solution or CO2/HCO3-buffered system (7.42 and 7.46, respectively). The pHi recovery following the induced-intracellular acidosis was blocked completely by removing [Na+]o, while only slowed (-63%) by adding HOE694 (a NHE1 specific inhibitor) in HEPES-buffered solution. The pHi recovery was inhibited entirely by removing [Na+]o, while adding HOE 694 pulse DIDS (an anion-transporter inhibitor) only slowed (-55%) the acid extrusion. Both in HEPES-buffered and CO2/HCO3-buffered system solution, the pHi recovery after induced-intracellular alkalosis was entirely blocked by removing [Cl-]o. Western blot analysis showed the isoforms of pHi regulators, including NHE1/2, NBCe1/n1, AE1/2/3/4 and CHE in the hDPSCs. CONCLUSIONS We demonstrate for the first time that resting pHi is significantly higher than 7.2 and meditates functionally by two Na+-dependent acid extruders (NHE and NBC), two Cl--dependent acid loaders (CHE and AE) and one Na+-independent acid extruder(s) in hDPSCs. These findings provide novel insight for basic and clinical treatment of dentistry.
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Affiliation(s)
- Gunng-Shinng Chen
- Division of Orthodontic, Dentofacial Orthopedic & Pediatric Dentistry, Department of Dentistry, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei 114, Taiwan
| | - Shiao-Pieng Lee
- Division of Oral and Maxillofacial Surgery, Department of Dentistry, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei 114, Taiwan
| | - Shu-Fu Huang
- Department of Clinical Pharmacy, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
| | - Shih-Chi Chao
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Pharmacology, National Defense Medical Center, Taipei 114, Taiwan
| | - Chung-Yi Chang
- Heart Center and Department of General Surgery, Cheng Hsin General Hospital, Taipei 112, Taiwan
| | - Gwo-Jang Wu
- Department of Obstetrics and Gynecology, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
| | - Chung-Hsing Li
- Division of Orthodontic, Dentofacial Orthopedic & Pediatric Dentistry, Department of Dentistry, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei 114, Taiwan
| | - Shih-Hurng Loh
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Pharmacology, National Defense Medical Center, Taipei 114, Taiwan.
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45
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Rácz R, Földes A, Bori E, Zsembery Á, Harada H, Steward MC, DenBesten P, Bronckers ALJJ, Gerber G, Varga G. No Change in Bicarbonate Transport but Tight-Junction Formation Is Delayed by Fluoride in a Novel Ameloblast Model. Front Physiol 2017; 8:940. [PMID: 29375389 PMCID: PMC5770627 DOI: 10.3389/fphys.2017.00940] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 11/06/2017] [Indexed: 01/17/2023] Open
Abstract
We have recently developed a novel in vitro model using HAT-7 rat ameloblast cells to functionally study epithelial ion transport during amelogenesis. Our present aims were to identify key transporters of bicarbonate in HAT-7 cells and also to examine the effects of fluoride exposure on vectorial bicarbonate transport, cell viability, and the development of transepithelial resistance. To obtain monolayers, the HAT-7 cells were cultured on Transwell permeable filters. We monitored transepithelial resistance (TER) as an indicator of tight junction formation and polarization. We evaluated intracellular pH changes by microfluorometry using the fluorescent indicator BCECF. Activities of ion transporters were tested by withdrawal of various ions from the bathing medium, by using transporter specific inhibitors, and by activation of transporters with forskolin and ATP. Cell survival was estimated by alamarBlue assay. Changes in gene expression were monitored by qPCR. We identified the activity of several ion transporters, NBCe1, NHE1, NKCC1, and AE2, which are involved in intracellular pH regulation and vectorial bicarbonate and chloride transport. Bicarbonate secretion by HAT-7 cells was not affected by acute fluoride exposure over a wide range of concentrations. However, tight-junction formation was inhibited by 1 mM fluoride, a concentration which did not substantially reduce cell viability, suggesting an effect of fluoride on paracellular permeability and tight-junction formation. Cell viability was only reduced by prolonged exposure to fluoride concentrations greater than 1 mM. In conclusion, cultured HAT-7 cells are functionally polarized and are able to transport bicarbonate ions from the basolateral to the apical fluid spaces. Exposure to 1 mM fluoride has little effect on bicarbonate secretion or cell viability but delays tight-junction formation, suggesting a novel mechanism that may contribute to dental fluorosis.
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Affiliation(s)
- Róbert Rácz
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Anna Földes
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Erzsébet Bori
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Ákos Zsembery
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | | | - Martin C Steward
- School of Medical Sciences, University of Manchester, Manchester, United Kingdom
| | - Pamela DenBesten
- Department of Orofacial Sciences, University of California, San Francisco, San Francisco, CA, United States
| | - Antonius L J J Bronckers
- Department of Oral Cell Biology, Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, Netherlands
| | - Gábor Gerber
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - Gábor Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
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46
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Celay J, Lozano T, Concepcion AR, Beltrán E, Rudilla F, García-Barchino MJ, Robles EF, Rabal O, de Miguel I, Panizo C, Casares N, Oyarzabal J, Prieto J, Medina JF, Lasarte JJ, Martínez-Climent JÁ. Targeting the anion exchanger 2 with specific peptides as a new therapeutic approach in B lymphoid neoplasms. Haematologica 2017; 103:1065-1072. [PMID: 29191842 PMCID: PMC6058773 DOI: 10.3324/haematol.2017.175687] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 11/24/2017] [Indexed: 12/20/2022] Open
Abstract
Regulatory T (Treg) cells can weaken antitumor immune responses, and inhibition of their function appears to be a promising therapeutic approach in cancer patients. Mice with targeted deletion of the gene encoding the Cl-/HCO3- anion exchanger AE2 (also termed SLC4A2), a membrane-bound carrier involved in intracellular pH regulation, showed a progressive decrease in the number of Treg cells. We therefore challenged AE2 as a potential target for tumor therapy, and generated linear peptides designed to bind the third extracellular loop of AE2, which is crucial for its exchange activity. Peptide p17AE2 exhibited optimal interaction ability and indeed promoted apoptosis in mouse and human Treg cells, while activating effector T-cell function. Interestingly, this linear peptide also induced apoptosis in different types of human leukemia, lymphoma and multiple myeloma cell lines and primary malignant samples, while it showed only moderate effects on normal B lymphocytes. Finally, a macrocyclic AE2 targeting peptide exhibiting increased stability in vivo was effective in mice xenografted with B-cell lymphoma. These data suggest that targeting the anion exchanger AE2 with specific peptides may represent an effective therapeutic approach in B-cell malignancies.
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Affiliation(s)
- Jon Celay
- Division of Hematological-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, CIBERONC, IDISNA, Pamplona, Spain
| | - Teresa Lozano
- Program of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Axel R Concepcion
- Division of Hepatology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.,Department of Pathology, New York University School of Medicine, New York, NY, USA
| | - Elena Beltrán
- Division of Hematological-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, CIBERONC, IDISNA, Pamplona, Spain.,Department of Pharmacology, University of Navarra, Pamplona, Spain
| | - Francesc Rudilla
- Program of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - María José García-Barchino
- Division of Hematological-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, CIBERONC, IDISNA, Pamplona, Spain
| | - Eloy F Robles
- Division of Hematological-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, CIBERONC, IDISNA, Pamplona, Spain
| | - Obdulia Rabal
- Small Molecule Discovery Platform and Molecular Therapeutics Program, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Irene de Miguel
- Small Molecule Discovery Platform and Molecular Therapeutics Program, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Carlos Panizo
- Department of Hematology, Clinica Universidad de Navarra, Pamplona, Spain
| | - Noelia Casares
- Program of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Julen Oyarzabal
- Small Molecule Discovery Platform and Molecular Therapeutics Program, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Jesús Prieto
- Program of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain.,Division of Hepatology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Juan F Medina
- Division of Hepatology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Juan José Lasarte
- Program of Immunology and Immunotherapy, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - José Ángel Martínez-Climent
- Division of Hematological-Oncology, Center for Applied Medical Research (CIMA), University of Navarra, CIBERONC, IDISNA, Pamplona, Spain
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47
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Ficici E, Faraldo-Gómez JD, Jennings ML, Forrest LR. Asymmetry of inverted-topology repeats in the AE1 anion exchanger suggests an elevator-like mechanism. J Gen Physiol 2017; 149:1149-1164. [PMID: 29167180 PMCID: PMC5715908 DOI: 10.1085/jgp.201711836] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/10/2017] [Indexed: 12/02/2022] Open
Abstract
Anion exchanger 1 catalyzes the transmembrane antiport of chloride and bicarbonate ions through a mechanism that has remained unclear. By modeling its inward-facing state and comparing it with the known outward-facing form, Ficici et al. hypothesize that this transporter features an elevator-like mechanism. The membrane transporter anion exchanger 1 (AE1), or band 3, is a key component in the processes of carbon-dioxide transport in the blood and urinary acidification in the renal collecting duct. In both erythrocytes and the basolateral membrane of the collecting-duct α-intercalated cells, the role of AE1 is to catalyze a one-for-one exchange of chloride for bicarbonate. After decades of biochemical and functional studies, the structure of the transmembrane region of AE1, which catalyzes the anion-exchange reaction, has finally been determined. Each protomer of the AE1 dimer comprises two repeats with inverted transmembrane topologies, but the structures of these repeats differ. This asymmetry causes the putative substrate-binding site to be exposed only to the extracellular space, consistent with the expectation that anion exchange occurs via an alternating-access mechanism. Here, we hypothesize that the unknown, inward-facing conformation results from inversion of this asymmetry, and we propose a model of this state constructed using repeat-swap homology modeling. By comparing this inward-facing model with the outward-facing experimental structure, we predict that the mechanism of AE1 involves an elevator-like motion of the substrate-binding domain relative to the nearly stationary dimerization domain and to the membrane plane. This hypothesis is in qualitative agreement with a wide range of biochemical and functional data, which we review in detail, and suggests new avenues of experimentation.
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Affiliation(s)
- Emel Ficici
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - José D Faraldo-Gómez
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Michael L Jennings
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Lucy R Forrest
- Computational Structural Biology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
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48
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The crystal structure of the regulatory domain of the human sodium-driven chloride/bicarbonate exchanger. Sci Rep 2017; 7:12131. [PMID: 28935959 PMCID: PMC5608694 DOI: 10.1038/s41598-017-12409-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 09/06/2017] [Indexed: 12/12/2022] Open
Abstract
The sodium-driven chloride/bicarbonate exchanger (NDCBE) is essential for maintaining homeostatic pH in neurons. The crystal structure at 2.8 Å resolution of the regulatory N-terminal domain of human NDCBE represents the first crystal structure of an electroneutral sodium-bicarbonate cotransporter. The crystal structure forms an equivalent dimeric interface as observed for the cytoplasmic domain of Band 3, and thus establishes that the consensus motif VTVLP is the key minimal dimerization motif. The VTVLP motif is highly conserved and likely to be the physiologically relevant interface for all other members of the SLC4 family. A novel conserved Zn2+-binding motif present in the N-terminal domain of NDCBE is identified and characterized in vitro. Cellular studies confirm the Zn2+ dependent transport of two electroneutral bicarbonate transporters, NCBE and NBCn1. The Zn2+ site is mapped to a cluster of histidines close to the conserved ETARWLKFEE motif and likely plays a role in the regulation of this important motif. The combined structural and bioinformatics analysis provides a model that predicts with additional confidence the physiologically relevant interface between the cytoplasmic domain and the transmembrane domain.
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49
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Varga G, DenBesten P, Rácz R, Zsembery Á. Importance of bicarbonate transport in pH control during amelogenesis - need for functional studies. Oral Dis 2017; 24:879-890. [PMID: 28834043 DOI: 10.1111/odi.12738] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 08/13/2017] [Indexed: 12/27/2022]
Abstract
Dental enamel, the hardest mammalian tissue, is produced by ameloblasts. Ameloblasts show many similarities to other transporting epithelia although their secretory product, the enamel matrix, is quite different. Ameloblasts direct the formation of hydroxyapatite crystals, which liberate large quantities of protons that then need to be buffered to allow mineralization to proceed. Buffering requires a tight pH regulation and secretion of bicarbonate by ameloblasts. Many investigations have used immunohistochemical and knockout studies to determine the effects of these genes on enamel formation, but up till recently very little functional data were available for mineral ion transport. To address this, we developed a novel 2D in vitro model using HAT-7 ameloblast cells. HAT-7 cells can be polarized and develop functional tight junctions. Furthermore, they are able to accumulate bicarbonate ions from the basolateral to the apical fluid spaces. We propose that in the future, the HAT-7 2D system along with similar cellular models will be useful to functionally model ion transport processes during amelogenesis. Additionally, we also suggest that similar approaches will allow a better understanding of the regulation of the cycling process in maturation-stage ameloblasts, and the pH sensory mechanisms, which are required to develop sound, healthy enamel.
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Affiliation(s)
- G Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - P DenBesten
- Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - R Rácz
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Á Zsembery
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
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50
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Qiu LY, Duan GL, Yan YF, Li YY, Wang H, Xiao L, Liao ZP, Chen HP. Sasanquasaponin induces increase of Cl‑/HCO3‑ exchange of anion exchanger 3 and promotes intracellular Cl‑ efflux in hypoxia/reoxygenation cardiomyocytes. Mol Med Rep 2017; 16:2953-2961. [PMID: 28677776 DOI: 10.3892/mmr.2017.6882] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 04/21/2017] [Indexed: 11/06/2022] Open
Abstract
Anion exchanger 3 (AE3) is known to serve crucial roles in maintaining intracellular chloride homeostasis by facilitating the reversible electroneutral exchange of Cl‑ for HCO3‑ across the plasma membrane. Our previous studies reported that sasanquasaponin (SQS) can inhibit hypoxia/reoxygenation (H/R)‑induced elevation of intracellular Cl‑ concentration ([Cl‑]i) and elicit cardioprotection by favoring Cl‑/HCO3‑ exchange of AE3. However, the molecular basis for SQS‑induced increase of Cl‑/HCO3‑ exchange of AE3 remains unclear. The present study demonstrated that SQS activates protein kinase Cε (PKCε) and stimulates the phosphorylation of AE3 in H9c2 cells. Notably, SQS‑induced AE3 phosphorylation was blocked by the PKCε selective inhibitor εV1‑2, and a S67A mutation of AE3, indicating that SQS could promote phosphorylation of Ser67 of AE3 via a PKCε‑dependent regulatory signaling pathway. Additionally, both inhibition of PKCε by εV1‑2 and S67A mutation of AE3 eradicated the SQS‑induced increase of AE3 activity, reversed the inhibitory effect of SQS on H/R‑induced elevation of [Cl‑]i, Ca2+ overload and generation of reactive oxygen species, and eliminated SQS‑induced cardioprotection. In conclusion, PKCε‑dependent phosphorylation of serine 67 on AE3 may be responsible for the increase of Cl‑/HCO3‑ exchange of AE3 and intracellular chloride efflux by SQS, and contributes to the cardioprotection of SQS against H/R in H9c2 cells.
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Affiliation(s)
- Ling-Yu Qiu
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Guang-Ling Duan
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Yu-Feng Yan
- Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, P.R. China
| | - Yuan-Yuan Li
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Huan Wang
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Ling Xiao
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Zhang-Ping Liao
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - He-Ping Chen
- The Key Laboratory of Basic Pharmacology, School of Pharmaceutical Science, Nanchang University, Nanchang, Jiangxi 330006, P.R. China
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