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Li W, Zhang Y, Zhao J, Yang T, Xie J. L-carnitine modified nanoparticles target the OCTN2 transporter to improve the oral absorption of jujuboside B. Eur J Pharm Biopharm 2024; 196:114185. [PMID: 38280469 DOI: 10.1016/j.ejpb.2024.114185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 01/11/2024] [Accepted: 01/21/2024] [Indexed: 01/29/2024]
Abstract
As a bioactive saponin derived from the seeds of Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chow, jujuboside B (JuB) shows great potential in anti-anxiety, anti-depression and improving learning and memory function. However, its oral bioavailability is very poor. In this study, a novel drug-loading nanoparticles system was prepared with polyethylene glycol and polylactic-co-glycolic acid copolymer (PEG-PLGA), and further modified with L-carnitine (LC) to target intestinal organic cation/carnitine transporter 2 (OCTN2) to improve the oral absorption of JuB. Under the optimized preparation conditions, the particle sizes of obtained JuB-PEG-PLGA nanoparticles (B-NPs) and LC modified B-NPs (LC-B-NPs) were 110.67 ± 11.37 nm and 134.00 ± 2.00 nm with the entrapment efficiency (EE%) 73.46 ± 1.26 % and 76.01 ± 2.10 %, respectively. The pharmacokinetics in SD rats showed that B-NPs and LC-B-NPs increased the bioavailability of JuB to 134.33 % and 159.04 % respectively. In Caco-2 cell model, the prepared nanoparticles significantly increased cell uptake of JuB, which verified the pharmacokinetic results. The absorption of LC-B-NPs mainly depended on OCTN2 transporter, and Na+ played an important role. Caveolin and clathrin were involved in the endocytosis of the two nanoparticles. In conclusion, both B-NPs and LC-B-NPs can improve the oral absorption of JuB, and the modification of LC can effectively target the OCTN2 transporter.
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Affiliation(s)
- Wei Li
- School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, People's Republic of China; School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, People's Republic of China
| | - Yanqing Zhang
- School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, People's Republic of China.
| | - Jing Zhao
- School of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin 300134, People's Republic of China
| | - Tan Yang
- School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, People's Republic of China
| | - Junbo Xie
- School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, Tianjin 301617, People's Republic of China.
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Chen M, Yi Y, Chen B, Zhang H, Dong M, Yuan L, Zhou H, Jiang H, Ma Z. Metformin inhibits OCTN1- and OCTN2-mediated hepatic accumulation of doxorubicin and alleviates its hepatotoxicity in mice. Toxicology 2024; 503:153757. [PMID: 38364893 DOI: 10.1016/j.tox.2024.153757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 02/18/2024]
Abstract
Doxorubicin (DOX) is a widely used antitumor agent; however, its clinical application is limited by dose-related organ damage. Because organic cation/carnitine transporters (OCTN1 and OCTN2), which are critical for DOX uptake, are highly expressed in hepatocytes, we aimed to elucidate the role of these transporters in hepatic DOX uptake. The results indicated that inhibitors and RNA interference both significantly reduced DOX accumulation in HepG2 and HepaRG cells, suggesting that OCTN1/2 contribute substantially to DOX uptake by hepatocytes. To determine whether metformin (MET, an inhibitor of OCTN1 and OCTN2) ameliorates DOX-induced hepatotoxicity, we conducted in vitro and in vivo studies. MET (1-100 μM) inhibited DOX (500 nM) accumulation and cytotoxicity in vitro in a concentration-dependent manner. Furthermore, intravenous MET administration at 250 or 500 mg/kg or by gavage at 50, 100, or 200 mg/kg reduced DOX (8 mg/kg) accumulation in a dose-dependent manner in the mouse liver and attenuated the release of alanine aminotransferase, aspartate aminotransferase, and carboxylesterase 1. Additionally, MET reduced the distribution of DOX in the heart, liver, and kidney and enhanced the urinary elimination of DOX; however, it did not increase the nephric toxicity of DOX. In conclusion, our study demonstrated that MET alleviates DOX hepatotoxicity by inhibiting OCTN1- and OCTN2-mediated DOX uptake in vitro (mouse hepatocytes and HepaRG or HepG2 cells) and in mice.
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Affiliation(s)
- Mingyang Chen
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Yaodong Yi
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Binxin Chen
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China; Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, School of Medicine, Westlake University, Hangzhou, China
| | - Hengbin Zhang
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Minlei Dong
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Luexiang Yuan
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Hui Zhou
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China; Jinhua Institute of Zhejiang University, Jinhua, China
| | - Huidi Jiang
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China; Jinhua Institute of Zhejiang University, Jinhua, China.
| | - Zhiyuan Ma
- Institute of Drug Metabolism and Pharmaceutical Analysis, Zhejiang Province Key Laboratory of Anti-Cancer Drug Research, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China; Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, School of Medicine, Westlake University, Hangzhou, China.
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Yang T, Liang N, Zhang J, Bai Y, Li Y, Zhao Z, Chen L, Yang M, Huang Q, Hu P, Wang Q, Zhang H. OCTN2 enhances PGC-1α-mediated fatty acid oxidation and OXPHOS to support stemness in hepatocellular carcinoma. Metabolism 2023; 147:155628. [PMID: 37315888 DOI: 10.1016/j.metabol.2023.155628] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 05/23/2023] [Accepted: 06/06/2023] [Indexed: 06/16/2023]
Abstract
BACKGROUND The Metabolic reprogramming of tumor cells plays a vital role in the progression of hepatocellular carcinoma. Organic cation/carnitine transporter 2 (OCTN2), a sodium-ion dependent carnitine transporter and a sodium-ion independent tetraethylammonium (TEA) transporter, has been reported to contribute tumor malignancies and metabolic dysregulation in renal and esophageal carcinoma. However, the role of lipid metabolism deregulation mediated by OCTN2 in HCC cells has not been clarified. METHODS Bioinformatics analyses and immunohistochemistry assay were employed to identify OCTN2 expression in HCC tissues. The correlation between OCTN2 expression and prognosis was elucidated through K-M survival analysis. The expression and function of OCTN2 were examined via the assays of western blotting, sphere formation, cell proliferation, migration and invasion. The mechanism of OCTN2-mediated HCC malignancies was investigated through RNA-seq and metabolomic analyses. Furthermore, xenograft tumor models based on HCC cells with different OCTN2 expression levels were conducted to analyze the tumorigenic and targetable role of OCTN2 in vivo. RESULTS We found that gradually focused OCTN2 was significantly upregulated in HCC and tightly associated with poor prognosis. Additionally, OCTN2 upregulation promoted HCC cells proliferation and migration in vitro and augmented the growth and metastasis of HCC. Moreover, OCTN2 promoted the cancer stem-like properties of HCC by increasing fatty acid oxidation and oxidative phosphorylation. Mechanistically, PGC-1α signaling participated in the HCC cancer stem-like properties mediated by OCTN2 overexpression, which is confirmed by in vitro and in vivo analyses. Furthermore, OCTN2 upregulation may be transcriptionally activated by YY1 in HCC. Particularly, treatment with mildronate, an inhibitor of OCTN2, showed a therapeutic influence on HCC in vitro and in vivo. CONCLUSIONS Our findings demonstrate that OCTN2 plays a critical metabolic role in HCC cancer stemness maintenance and HCC progression, providing evidence for OCTN2 as a promising target for HCC therapy.
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Affiliation(s)
- Tao Yang
- Department of Pain Treatment, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, China
| | - Ning Liang
- Department of General Surgery, The 75th Group Army Hospital, Dali 671000, China; Department of General Surgery, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, China
| | - Jiahao Zhang
- Department of Thoracic Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yaxing Bai
- Department of Dermatology, XiJing Hospital, Xi'an, Shaanxi 710032, China
| | - Yuedan Li
- Department of Pharmacy, General Hospital of Central Theater Command, Wuhan 430010, China
| | - Zifeng Zhao
- Department of Pain Treatment, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, China
| | - Liusheng Chen
- Clinical Research Center, The 75th Group Army Hospital, Dali, Yunnan 671000, China
| | - Min Yang
- Department of General Surgery, The 75th Group Army Hospital, Dali 671000, China
| | - Qian Huang
- Clinical Research Center, The 75th Group Army Hospital, Dali, Yunnan 671000, China
| | - Pan Hu
- Department of Anesthesiology, the 920 Hospital of Joint Logistic Support Force of Chinese PLA, Kunming, Yunnan 650500, China.
| | - Qian Wang
- Department of General Surgery, The First Affiliated Hospital, Zhengzhou University, Zhengzhou, Henan 450052, China.
| | - Hongxin Zhang
- Department of Pain Treatment, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710038, China; Department of Intervention Therapy, The Second Affiliated Hospital, Shaanxi University of Chinese Medicine, Xianyang 712046, China.
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Yi Y, Zhang H, Chen M, Chen B, Chen Y, Li P, Zhou H, Ma Z, Jiang H. Inhibition of multiple uptake transporters in cardiomyocytes/mitochondria alleviates doxorubicin-induced cardiotoxicity. Chem Biol Interact 2023; 382:110627. [PMID: 37453608 DOI: 10.1016/j.cbi.2023.110627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/30/2023] [Accepted: 07/10/2023] [Indexed: 07/18/2023]
Abstract
Doxorubicin (DOX) has been widely used to treat various tumors; however, DOX-induced cardiotoxicity limits its utilization. Since high accumulation of DOX in cardiomyocytes/mitochondria is the key reason, we aimed to clarify the mechanisms of DOX uptake and explore whether selectively inhibiting DOX uptake transporters would attenuate DOX accumulation and cardiotoxicity. Our results demonstrated that OCTN1/OCTN2/PMAT (organic cation/carnitine transporter 1/2 or plasma membrane monoamine transporter), especially OCTN2, played crucial roles in DOX uptake in cardiomyocytes, while OCTN2 and OCTN1 contributed to DOX transmembrane transport in mitochondria. Metformin (1-100 μM) concentration-dependently reduced DOX (5 μM for accumulation, 500 nM for cytotoxicity) concentration and toxicity in cardiomyocytes/mitochondria via inhibition of OCTN1-, OCTN2- and PMAT-mediated DOX uptake but did not affect its efflux. Furthermore, metformin (iv: 250 and 500 mg/kg or ig: 50, 100 and 200 mg/kg) could dose-dependently reduce DOX (8 mg/kg) accumulation in mouse myocardium and attenuated its cardiotoxicity. In addition, metformin (1-100 μM) did not impair DOX efficacy in breast cancer or leukemia cells. In conclusion, our study clarified the role of multiple transporters, especially OCTN2, in DOX uptake in cardiomyocytes/mitochondria; metformin alleviated DOX-induced cardiotoxicity without compromising its antitumor efficacy by selective inhibition of multiple transporters mediated DOX accumulation in myocardium/mitochondria.
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Affiliation(s)
- Yaodong Yi
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Hengbin Zhang
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Mingyang Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Binxin Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Yingchun Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Ping Li
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | - Hui Zhou
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China; Jinhua Institute of Zhejiang University, PR China
| | - Zhiyuan Ma
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China; Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, PR China.
| | - Huidi Jiang
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China; Jinhua Institute of Zhejiang University, PR China.
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Dinarvand N, Karimi F, Azizi R, Rastaghi S, Sheikhi A, Pourfarzam M. Evaluation of the gene encoding carnitine transporter ( OCTN2/SLC22A5) expression in human breast cancer and its association with clinicopathological characteristics. Mol Biol Rep 2023; 50:2061-6. [PMID: 36539562 DOI: 10.1007/s11033-022-08152-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 11/23/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Fatty acid oxidation (FAO) is a major energy-generating process in the mitochondria and supports proliferation, growth, and survival of cancer cells. L-Carnitine is an essential co-factor for carrying long-chain fatty acids into the mitochondria. The entry of l-carnitine across cell membrane is regulated by OCTN2 (SLC22A5). Thus, it can plays a significant role in the mitochondrial fatty acid oxidation. This study aimed to evaluate the OCTN2 expression and its association with clinicopathological characteristics in breast cancer. METHODS In this work, OCTN2 was examined in 54 pairs of fresh samples of breast cancer (BC) and adjacent noncancerous tissue using quantitative real-time polymerase chain reaction and immunohistochemistry (IHC). The IHC approach was also used to investigate the expression of additional clinicopathological features. RESULTS The present research findings revealed that the relative expression of OCTN2 in BC tissues was substantially higher than the adjacent normal tissues. This up-regulation was correlated positively with tumor size and Ki-67 and negatively with the progesterone receptor (PR) status, providing evidence of the opposite effects of OCTN2 and PR on tumor development. CONCLUSION The study shows that the OCTN2 expression in BC patients may be used as a prognostic biomarker and a tumor oncogene. As a result, it could be considered a possible therapeutic target. Nevertheless, the significance of the findings needs to be confirmed by further studies.
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Wall BT, Machin D, Dunlop MV, Stephens FB. Caffeine ingestion stimulates plasma carnitine clearance in humans. Physiol Rep 2023; 11:e15615. [PMID: 36806708 PMCID: PMC9938004 DOI: 10.14814/phy2.15615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 02/20/2023] Open
Abstract
Increasing skeletal muscle carnitine content can manipulate fuel metabolism and improve exercise performance. Intravenous insulin infusion during hypercarnitinemia increases plasma carnitine clearance and Na+ -dependent muscle carnitine accretion, likely via stimulating Na+ /K+ ATPase pump activity. We hypothesized that the ingestion of high-dose caffeine, also known to stimulate Na+ /K+ ATPase activity, would stimulate plasma carnitine clearance during hypercarnitinemia in humans. In a randomized placebo-controlled study, six healthy young adults (aged 24 ± 5 years, height 175 ± 8 cm, and weight 70 ± 13 kg) underwent three 5-h laboratory visits involving the primed continuous intravenous infusion of l-carnitine (CARN and CARN + CAFF) or saline (CAFF) in parallel with ingestion of caffeine (CARN + CAFF and CAFF) or placebo (CARN) at 0, 2, 3, and 4 h. Regular blood samples were collected to determine concentrations of blood Na+ and K+ , and plasma carnitine and caffeine, concentrations. Caffeine ingestion (i.e., CAFF and CARN + CAFF conditions) and l-carnitine infusion (i.e., CARN and CARN + CAFF) elevated steady-state plasma caffeine (to ~7 μg·mL-1 ) and carnitine (to ~400 μmol·L-1 ) concentrations, respectively, throughout the 5 h infusions. Plasma carnitine concentration was ~15% lower in CARN + CAFF compared with CARN during the final 90 min of the infusion (at 210 min, 356 ± 96 vs. 412 ± 94 μmol·L-1 ; p = 0.0080: at 240 min, 350 ± 91 vs. 406 ± 102 μmol·L-1 ; p = 0.0079: and at 300 min, 357 ± 91 vs. 413 ± 110 μmol·L-1 ; p = 0.0073, respectively). Blood Na+ concentrations were greater in CAFF and CARN + CAFF compared with CARN. Ingestion of high-dose caffeine stimulates plasma carnitine clearance during hypercarnitinemia, likely via increased Na+ /K+ ATPase activity. Carnitine co-ingestion with caffeine may represent a novel muscle carnitine loading strategy in humans, and therefore manipulate skeletal muscle fuel metabolism and improve exercise performance.
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Affiliation(s)
- Benjamin T. Wall
- Department of Public Health and Sport SciencesUniversity of ExeterExeterUK
| | - David Machin
- Department of Public Health and Sport SciencesUniversity of ExeterExeterUK
| | - Mandy V. Dunlop
- Department of Public Health and Sport SciencesUniversity of ExeterExeterUK
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Wang X, Hu L, Wang C, He B, Fu Z, Jin C, Jin Y. Cross-generational effects of maternal exposure to imazalil on anaerobic components and carnitine absorption associated with OCTN2 expression in mice. Chemosphere 2022; 308:136542. [PMID: 36150497 DOI: 10.1016/j.chemosphere.2022.136542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/23/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Imazalil (IMZ) is a fungicide recommended by the Chinese ministry of agriculture. However, recent study was observed high level of IMZ by dietary exposure in pregnant women. To determine the cross-generational effects, C57BL/6 mice were exposed to IMZ at dietary levels of 0, 0.025‰, and 0.25‰ during the gestation and lactation periods. Then, we assessed the changes in growth phenotypes, carnitine levels, and gut microbiota in F0, F1 or F2 generations. The growth phenotypes of dams didn't observe significant difference, but there were significant changes in the offspring. Plasma samples revealed low levels of free carnitine (C0), long-chain acyl-carnitines and total carnitine. In particular, C0 may be regarded as relatively potential, specific markers by maternal IMZ exposure. Caco2 cell culture and animal experiment confirmed IMZ affected carnitine absorption through the organic cation transporter type-2 (OCTN2) protein encoded by solute carrier family 22A member 5 (SLC22A5) gene in colon. Maternal IMZ exposure also had a greater effect on gut microbiota in offspring, especially anaerobic bacteria, which positively correlated with C0 and acyl-carnitines. These results suggested that maternal IMZ exposure affected carnitine absorption through OCTN2 protein, which led to the decline of anaerobic bacteria and unbalanced intestinal homeostasis.
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Affiliation(s)
- Xiaofang Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Lingyu Hu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Caiyun Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Bingnan He
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Zhengwei Fu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Cuiyuan Jin
- Institute of Translational Medicine, Zhejiang Shuren University, Hangzhou, 310015, China.
| | - Yuanxiang Jin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China.
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Novakova K, Török M, Panajatovic M, Bouitbir J, Duong FHT, Handschin C, Krähenbühl S. PGC-1α and MEF2 Regulate the Transcription of the Carnitine Transporter OCTN2 Gene in C2C12 Cells and in Mouse Skeletal Muscle. Int J Mol Sci 2022; 23:12304. [PMID: 36293168 DOI: 10.3390/ijms232012304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/04/2022] [Accepted: 10/05/2022] [Indexed: 11/05/2022] Open
Abstract
OCTN2 (SLC22A5) is a carnitine transporter whose main function is the active transport of carnitine into cells. In skeletal muscle and other organs, the regulation of the SLC22A5 gene transcription has been shown to depend on the nuclear transcription factor PPAR-α. Due to the observation that the muscle OCTN2 mRNA level is maintained in PPAR-α knock-out mice and that PGC-1α overexpression in C2C12 myoblasts increases OCTN2 mRNA expression, we suspected additional regulatory pathways for SLC22A5 gene transcription. Indeed, we detected several binding sites of the myocyte-enhancing factor MEF2 in the upstream region of the SLC22A5 gene, and MEF2C/MEF2D stimulated the activity of the OCTN2 promoter in gene reporter assays. This stimulation was increased by PGC-1α and was blunted for a SLC22A5 promoter fragment with a mutated MEF2 binding site. Further, we demonstrated the specific binding of MEF2 to the SLC22A5 gene promoter, and a supershift of the MEF2/DNA complex in electrophoretic mobility shift assays. In immunoprecipitation experiments, we could demonstrate the interaction between PGC-1α and MEF2. In addition, SB203580, a specific inhibitor of p38 MAPK, blocked and interferon-γ stimulated the transcriptional activity of the SLC22A5 gene promoter. Finally, mice with muscle-specific overexpression of OCTN2 showed an increase in OCTN2 mRNA and protein expression in skeletal muscle. In conclusion, we detected and characterized a second stimulatory pathway of SLC22A5 gene transcription in skeletal muscle, which involves the nuclear transcription factor MEF2 and co-stimulation by PGC-1α and which is controlled by the p38 MAPK signaling cascade.
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Zhang P, Azad P, Engelhart DC, Haddad GG, Nigam SK. SLC22 Transporters in the Fly Renal System Regulate Response to Oxidative Stress In Vivo. Int J Mol Sci 2021; 22:13407. [PMID: 34948211 DOI: 10.3390/ijms222413407] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 12/12/2022] Open
Abstract
Several SLC22 transporters in the human kidney and other tissues are thought to regulate endogenous small antioxidant molecules such as uric acid, ergothioneine, carnitine, and carnitine derivatives. These transporters include those from the organic anion transporter (OAT), OCTN/OCTN-related, and organic cation transporter (OCT) subgroups. In mammals, it has been difficult to show a clear in vivo role for these transporters during oxidative stress. Ubiquitous knockdowns of related Drosophila SLC22s-including transporters homologous to those previously identified by us in mammals such as the "Fly-Like Putative Transporters" FLIPT1 (SLC22A15) and FLIPT2 (SLC22A16)-have shown modest protection against oxidative stress. However, these fly transporters tend to be broadly expressed, and it is unclear if there is an organ in which their expression is critical. Using two tissue-selective knockdown strategies, we were able to demonstrate much greater and longer protection from oxidative stress compared to previous whole fly knockdowns as well as both parent and WT strains (CG6126: p < 0.001, CG4630: p < 0.01, CG16727: p < 0.0001 and CG6006: p < 0.01). Expression in the Malpighian tubule and likely other tissues as well (e.g., gut, fat body, nervous system) appear critical for managing oxidative stress. These four Drosophila SLC22 genes are similar to human SLC22 transporters (CG6126: SLC22A16, CG16727: SLC22A7, CG4630: SLC22A3, and CG6006: SLC22A1, SLC22A2, SLC22A3, SLC22A6, SLC22A7, SLC22A8, SLC22A11, SLC22A12 (URAT1), SLC22A13, SLC22A14)-many of which are highly expressed in the kidney. Consistent with the Remote Sensing and Signaling Theory, this indicates an important in vivo role in the oxidative stress response for multiple SLC22 transporters within the fly renal system, perhaps through interaction with SLC22 counterparts in non-renal tissues. We also note that many of the human relatives are well-known drug transporters. Our work not only indicates the importance of SLC22 transporters in the fly renal system but also sets the stage for in vivo studies by examining their role in mammalian oxidative stress and organ crosstalk.
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Sun D, Chen Q, Gai Z, Zhang F, Yang X, Hu W, Chen C, Yang G, Hörmann S, Kullak-Ublick GA, Visentin M. The Role of the Carnitine/Organic Cation Transporter Novel 2 in the Clinical Outcome of Patients With Locally Advanced Esophageal Carcinoma Treated With Oxaliplatin. Front Pharmacol 2021; 12:684545. [PMID: 34603016 PMCID: PMC8481660 DOI: 10.3389/fphar.2021.684545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 08/18/2021] [Indexed: 01/25/2023] Open
Abstract
Esophageal cancer is the ninth most common malignancy worldwide, ranking sixth in mortality. Platinum-based chemotherapy is commonly used for treating locally advanced esophageal cancer, yet it is ineffective in a large portion of patients. There is a need for reliable molecular markers with direct clinical application for a prospective selection of patients who can benefit from chemotherapy and patients in whom toxicity is likely to outweigh the benefit. The cytotoxic activity of platinum derivatives largely depends on the uptake and accumulation into cells, primarily by organic cation transporters (OCTs). The aim of the study was to investigate the impact of OCT expression on the clinical outcome of patients with esophageal cancer treated with oxaliplatin. Twenty patients with esophageal squamous cell carcinoma (SCC) were prospectively enrolled and surgical specimens used for screening OCT expression level by western blotting and/or immunostaining, and for culture of cancer cells. Sixty-seven patients with SCC who received oxaliplatin and for whom follow-up was available were retrospectively assessed for organic cation/carnitine transporter 2 (OCTN2) expression by real time RT-PCR and immunostaining. OCTN2 staining was also performed in 22 esophageal adenocarcinomas. OCTN2 function in patient-derived cancer cells was evaluated by assessing L-carnitine uptake and sensitivity to oxaliplatin. The impact of OCTN2 on oxaliplatin activity was also assessed in HEK293 cells overexpressing OCTN2. OCTN2 expression was higher in tumor than in normal tissues. In patient-derived cancer cells and HEK293 cells, the expression of OCTN2 sensitized to oxaliplatin. Patients treated with oxaliplatin who had high OCTN2 level in the tumor tissue had a reduced risk of recurrence and a longer survival time than those with low expression of OCTN2 in tumor tissue. In conclusion, OCTN2 is expressed in esophageal cancer and it is likely to contribute to the accumulation and cytotoxic activity of oxaliplatin in patients with esophageal carcinoma treated with oxaliplatin.
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Affiliation(s)
- Dongfeng Sun
- Department of Thoracic Surgery, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Medicine and Health Key Laboratory of Emergency Medicine, Shandong Lung Cancer Institute, Shandong Institute of Respiratory Diseases, Jinan, China
| | - Qingfa Chen
- The Institute for Tissue Engineering and Regenerative Medicine, Liaocheng University/Liaocheng People's Hospital, Liaocheng, China
| | - Zhibo Gai
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Fengxia Zhang
- Department of Thoracic Surgery, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Medicine and Health Key Laboratory of Emergency Medicine, Shandong Lung Cancer Institute, Shandong Institute of Respiratory Diseases, Jinan, China
| | - Xiaoqing Yang
- Department of Pathology, The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Wensi Hu
- Department of Thoracic Surgery, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Medicine and Health Key Laboratory of Emergency Medicine, Shandong Lung Cancer Institute, Shandong Institute of Respiratory Diseases, Jinan, China
| | - Chengyu Chen
- Department of Thoracic Surgery, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Shandong Medicine and Health Key Laboratory of Emergency Medicine, Shandong Lung Cancer Institute, Shandong Institute of Respiratory Diseases, Jinan, China
| | - Guangjie Yang
- Department of Nuclear Medicine, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Severin Hörmann
- Department of Pathology and Molecular Pathology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Gerd A Kullak-Ublick
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Michele Visentin
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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11
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Kou L, Sun R, Xiao S, Cui X, Sun J, Ganapathy V, Yao Q, Chen R. OCTN2-targeted nanoparticles for oral delivery of paclitaxel: differential impact of the polyethylene glycol linker size on drug delivery in vitro, in situ, and in vivo. Drug Deliv 2020; 27:170-179. [PMID: 31913724 PMCID: PMC6968687 DOI: 10.1080/10717544.2019.1710623] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Targeted nanocarriers have shown great promise in drug delivery because of optimized drug
behavior and improved therapeutic efficacy. How to improve the targeting efficiency of
nanocarriers for the maximum possible drug delivery is a critical issue. Here we developed
L-carnitine-conjugated nanoparticles targeting the carnitine transporter OCTN2 on
enterocytes for improved oral absorption. As a variable, we introduced various lengths of
the polyethylene glycol linker (0, 500, 1000, and 2000) between the nanoparticle surface
and the ligand (CNP, C5NP, C10NP and C20NP) to improve the ligand flexibility, and
consequently for more efficient interaction with the transporter, to enhance the oral
delivery of the cargo load into cells. An increased absorption was observed in cellular
uptake in vitro and in intestinal perfusion assay in
situ when the polyethylene glycol was introduced to link L-carnitine to the
nanoparticles; the highest absorption was achieved with C10NP. In contrast, the linker
decreased the absorption efficiency in vivo. As the presence or absence
of the mucus layer was the primary difference between in vitro/in
situ versus in vivo, the presence of this layer was the likely
reason for this differential effect. In summary, the size of the polyethylene glycol
linker improved the absorption in vitro and in situ, but
interfered with the absorption in vivo. Even though this strategy of
increasing the ligand flexibility with the variable size of the polyethylene glycol failed
to increase oral absorption in vivo, this approach is likely to be useful
for enhanced cellular uptake following intravenous administration of the nanocarriers.
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Affiliation(s)
- Longfa Kou
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Rui Sun
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Shuyi Xiao
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xiao Cui
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jin Sun
- Department of Pharmaceutics, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, China
| | - Vadivel Ganapathy
- Department of Cell Biology and Biochemistry, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Qing Yao
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Ruijie Chen
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
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12
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Qi C, Zhou J, Wang Z, Fang X, Li D, Jin Y, Song J. Cigarette smoke extract combined with lipopolysaccharide reduces OCTN1/2 expression in human alveolar epithelial cells in vitro and rat lung in vivo under inflammatory conditions. Int Immunopharmacol 2020; 87:106812. [PMID: 32707498 DOI: 10.1016/j.intimp.2020.106812] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 06/25/2020] [Accepted: 07/13/2020] [Indexed: 12/21/2022]
Abstract
Organic cation transporter 1/2 (OCTN1/2) play important roles in the transport of drugs related to pulmonary inflammatory diseases. Nevertheless, the involvement of inflammation induced by cigarette smoke extract (CSE) combined with lipopolysaccharide (LPS) in the regulation of OCTN1/2 is not fully understood. In this study, CSE combined with LPS was used to establish inflammation models in vitro and in vivo. Our study found that the expression of OCTN1/2 was downregulated in rat lung in vivo and in a human alveolar cell line in vitro after treatment with CSE and LPS compared with the control group, while the expression of inflammatory factors was upregulated. After treatment with ipratropium bromide (IB) or dexamethasone (DEX), the expression of OCTN1/2 was upregulated compared with that in the CSE-LPS model group, while the expression of inflammatory factors was significantly downregulated. After administration of the NF-κB inhibitor PDTC on the basis of the inflammatory status, the expression of OCTN1/2 was upregulated in the treated group compared with the CSE-LPS model group, while the expression of phospho-p65, phospho-IκBα and inflammatory factors was significantly downregulated. We further added the NF-κB agonist HSP70 and found a result that the exact opposite of that observed with PDTC. Our findings show that CSE combined with LPS can downregulate the expression of OCTN1/2 under inflammatory conditions, and that the downregulation of OCTN1/2 expression may partially occur via the NF-κB signaling pathway.
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Affiliation(s)
- Chuanzong Qi
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China
| | - Jian Zhou
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China
| | - Zihao Wang
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China
| | - Xin Fang
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China
| | - Dalang Li
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China
| | - Yong Jin
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China
| | - Jue Song
- Institute for Anhui Province Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, Hefei, China; Institute for the Key Laboratory of Anti-inflammatory and Immune Medicines, Ministry of Education, Hefei, China.
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13
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Li P, Wang Y, Luo J, Zeng Q, Wang M, Bai M, Zhou H, Wang J, Jiang H. Downregulation of OCTN2 by cytokines plays an important role in the progression of inflammatory bowel disease. Biochem Pharmacol 2020; 178:114115. [PMID: 32579962 DOI: 10.1016/j.bcp.2020.114115] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 12/18/2022]
Abstract
Inflammatory bowel diseases (IBD) are characterized by chronic relapsing disorders of the gastrointestinal tract. OCTN2 (SLC22A5) and its substrate l-carnitine (l-Car) play crucial roles in maintaining normal intestinal function. An aim of this study was to delineate the expression alteration of OCTN2 in IBD and its underlying mechanism. We also investigated the impact of OCTN2 on IBD progression and the possibility of improving IBD through OCTN2 regulation. Our results showed decreased OCTN2 expression levels and l-Car content in inflamed colon tissues of IBD patients and mice, which negatively correlated with the degree of colonic inflammation in IBD mice. Mixed proinflammatory cytokines TNF-α, IL-1β and IFNγ downregulated the expression of OCTN2 and subsequently reduced the l-Car content through PPARγ/RXRα pathways in FHC cells. OCTN2 silencing reduced the proliferation rate of the colon cells, whereas OCTN2 overexpression increased the proliferation rate. Furthermore, the ability of PPARγ agonist, luteolin, to increase OCTN2 expression resulted in the alleviation of colonic inflammatory responses. In conclusion, OCTN2 was downregulated in IBD by proinflammatory cytokines via the PPARγ/RXRα pathways, which reduced l-Car concentration and subsequently induced IBD deterioration. Upregulation of OCTN2 by the PPARγ agonist alleviated colonic inflammation. Our findings suggest that, OCTN2 may serve as a therapeutic target for IBD therapy.
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Affiliation(s)
- Ping Li
- Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Yuqing Wang
- Hangzhou Translational Medicine Research Center, Hangzhou First People's Hospital, Hangzhou, China; Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Jun Luo
- Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Qingquan Zeng
- College of Medicine, Zhejiang University, Hangzhou, China; Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Miaojuan Wang
- Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Mengru Bai
- Hangzhou Translational Medicine Research Center, Hangzhou First People's Hospital, Hangzhou, China; Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Hui Zhou
- Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
| | - Jinhai Wang
- College of Medicine, Zhejiang University, Hangzhou, China.
| | - Huidi Jiang
- Laboratory of Drug Metabolism and Pharmaceutical Analysis, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China.
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14
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Müller OJ, Heckmann MB, Ding L, Rapti K, Rangrez AY, Gerken T, Christiansen N, Rennefahrt UEE, Witt H, González Maldonado S, Ternes P, Schwab DM, Ruf T, Hille S, Remes A, Jungmann A, Weis TM, Kreußer JS, Gröne HJ, Backs J, Schatz P, Katus HA, Frey N. Comprehensive plasma and tissue profiling reveals systemic metabolic alterations in cardiac hypertrophy and failure. Cardiovasc Res 2020; 115:1296-1305. [PMID: 30418544 DOI: 10.1093/cvr/cvy274] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/23/2018] [Accepted: 11/08/2018] [Indexed: 01/30/2023] Open
Abstract
AIMS Heart failure is characterized by structural and metabolic cardiac remodelling. The aim of the present study is to expand our understanding of the complex metabolic alterations in the transition from pathological hypertrophy to heart failure and exploit the results from a translational perspective. METHODS AND RESULTS Mice were subjected to transverse aortic constriction (TAC) or sham surgery and sacrificed 2 weeks, 4 weeks, or 6 weeks after the procedure. Samples from plasma, liver, skeletal muscle, and heart were collected and analysed using metabolomics. Cardiac samples were also analysed by transcriptional profiling. Progressive alterations of key cardiac metabolic pathways and gene expression patterns indicated impaired mitochondrial function and a metabolic switch during transition to heart failure. Similar to the heart, liver, and skeletal muscle revealed significant metabolic alterations such as depletion of essential fatty acids and glycerolipids in late stages of heart failure. Circulating metabolites, particularly fatty acids, reflected cardiac metabolic defects, and deteriorating heart function. For example, inverse correlation was found between plasma and the heart levels of triacylglycerol (C18:1, C18:2, C18:3), and sphingomyelin (d18:1, C23:0) already at an early stage of heart failure. Interestingly, combining metabolic and transcriptional data from cardiac tissue revealed that decreased carnitine shuttling and transportation preceded mitochondrial dysfunction. We, thus, studied the therapeutic potential of OCTN2 (Organic Cation/Carnitine Transporter 2), an important factor for carnitine transportation. Cardiac overexpression of OCTN2 using an adeno-associated viral vector significantly improved ejection fraction and reduced interstitial fibrosis in mice subjected to TAC. CONCLUSION Comprehensive plasma and tissue profiling reveals systemic metabolic alterations in heart failure, which can be used for identification of novel biomarkers and potential therapeutic targets.
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Affiliation(s)
- Oliver J Müller
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Markus B Heckmann
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Lin Ding
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Kleopatra Rapti
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Ashraf Y Rangrez
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Str. 3, Kiel, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Germany
| | - Thomas Gerken
- Metanomics Health GmbH, Tegeler Weg 33, Berlin, Germany
| | | | | | - Henning Witt
- Metanomics GmbH, Tegeler Weg 33, Berlin, Germany
| | | | | | - Dominic M Schwab
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Theresa Ruf
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Susanne Hille
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Str. 3, Kiel, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Germany
| | - Anca Remes
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Str. 3, Kiel, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Germany
| | - Andreas Jungmann
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Tanja M Weis
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Julia S Kreußer
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany.,Department of Molecular Cardiology and Epigenetics, University of Heidelberg, Im Neuenheimer Feld 669, Heidelberg, Germany
| | - Hermann-Josef Gröne
- Department of Cellular and Molecular Pathology, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg, Germany
| | - Johannes Backs
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany.,Department of Molecular Cardiology and Epigenetics, University of Heidelberg, Im Neuenheimer Feld 669, Heidelberg, Germany
| | | | - Hugo A Katus
- Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, Heidelberg, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Germany
| | - Norbert Frey
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Str. 3, Kiel, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Germany
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15
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Oppedisano F, Muscoli C, Musolino V, Carresi C, Macrì R, Giancotta C, Bosco F, Maiuolo J, Scarano F, Paone S, Nucera S, Zito MC, Scicchitano M, Ruga S, Ragusa M, Palma E, Tavernese A, Mollace R, Bombardelli E, Mollace V. The Protective Effect of Cynara Cardunculus Extract in Diet-Induced NAFLD: Involvement of OCTN1 and OCTN2 Transporter Subfamily. Nutrients 2020; 12:E1435. [PMID: 32429274 PMCID: PMC7284543 DOI: 10.3390/nu12051435] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/05/2020] [Accepted: 05/08/2020] [Indexed: 12/12/2022] Open
Abstract
Hyperlipidemia and insulin-resistance are often associated with Non-Alcoholic Fatty Liver Disease (NAFLD) thereby representing a true issue worldwide due to increased risk of developing cardiovascular and systemic disorders. Although clear evidence suggests that circulating fatty acids contribute to pathophysiological mechanisms underlying NAFLD and hyperlipidemia, further studies are required to better identify potential beneficial approaches for counteracting such a disease. Recently, several artichoke extracts have been used for both reducing hyperlipidemia, insulin-resistance and NAFLD, though the mechanism is unclear. Here we used a wild type of Cynara Cardunculus extract (CyC), rich in sesquiterpens and antioxidant active ingredients, in rats fed a High Fat Diet (HFD) compared to a Normal Fat Diet (NFD). In particular, in rats fed HFD for four consecutive weeks, we found a significant increase of serum cholesterol, triglyceride and serum glucose. This effect was accompanied by increased body weight and by histopathological features of liver steatosis. The alterations of metabolic parameters found in HFDs were antagonised dose-dependently by daily oral supplementation of rats with CyC 10 and 20 mg/kg over four weeks, an effect associated to significant improvement of liver steatosis. The effect of CyC (20 mg/kg) was also associated to enhanced expression of both OCTN1 and OCTN2 carnitine-linked transporters. Thus, present data suggest a contribution of carnitine system in the protective effect of CyC in diet-induced hyperlipidemia, insulin-resistance and NAFLD.
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Affiliation(s)
- Francesca Oppedisano
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Carolina Muscoli
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
- San Raffaele IRCCS, 00199 Rome, Italy
| | - Vincenzo Musolino
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Cristina Carresi
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Roberta Macrì
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Caterina Giancotta
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Francesca Bosco
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Jessica Maiuolo
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Federica Scarano
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Sara Paone
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Saverio Nucera
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Maria Caterina Zito
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Miriam Scicchitano
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Stefano Ruga
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Monica Ragusa
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Ernesto Palma
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Annamaria Tavernese
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Rocco Mollace
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Ezio Bombardelli
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
| | - Vincenzo Mollace
- Institute of Research for Food Safety & Health, Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy; (F.O.); (C.M.); (V.M.); (C.C.); (R.M.); (C.G.); (F.B.); (J.M.); (F.S.); (S.P.); (S.N.); (M.C.Z.); (M.S.); (S.R.); (M.R.); (E.P.); (A.T.); (R.M.); (E.B.)
- San Raffaele IRCCS, 00199 Rome, Italy
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16
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Lin Y, Xu H, Zhou D, Hu Z, Zhang C, Hu L, Zhang Y, Zhu L, Lu B, Zhang T, Huang X. Screening 3.4 million newborns for primary carnitine deficiency in Zhejiang Province, China. Clin Chim Acta 2020; 507:199-204. [PMID: 32371215 DOI: 10.1016/j.cca.2020.04.039] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/31/2022]
Abstract
Testing for primary carnitine deficiency (PCD) has been implemented in many newborn screening (NBS) programs, but few large-scale studies on NBS for PCD have been reported in China. This study aimed to assess the incidence and biochemical, clinical, and genetic characteristics of PCD discovered by NBS. Dried blood spots from newborns were analyzed by tandem mass spectrometry (MS/MS) and suspected positive patients were further tested using molecular genetic analysis. Infants who carried two variants in SLC22A5 or those with extremely low free carnitine levels during recall were referred for follow-up and treatment. Over 3.4 million newborns were screened and 113 newborns were diagnosed with PCD, yielding a positive predictive value of 1.93%. In addition, 63 mothers with PCD were identified. The incidence of PCD in newborns and mothers in Zhejiang was 1:30,182 and 1:54,137, respectively. Thirty-seven distinct variants were identified in SLC22A5 of which 10 were novel. c.1400C > G (p.S467C) was the most prevalent variant in both newborns and mothers with PCD, while c.760C > T (p.R254*), which is reportedly common in other Chinese regions, was rarely detected in maternal PCD patients. This study reports the largest series of patients with PCD detected by NBS and identifies 10 novel variants, expanding the variant spectrum of SLC22A5.
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17
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Grünert SC, Tucci S, Schumann A, Schwendt M, Gramer G, Hoffmann GF, Erbel M, Stiller B, Spiekerkoetter U. Primary carnitine deficiency - diagnosis after heart transplantation: better late than never! Orphanet J Rare Dis 2020; 15:87. [PMID: 32276632 PMCID: PMC7146900 DOI: 10.1186/s13023-020-01371-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/31/2020] [Indexed: 12/30/2022] Open
Abstract
Background Primary carnitine deficiency due to mutations in the SLC22A5 gene is a rare but well-treatable metabolic disorder that puts patients at risk for metabolic decompensations, skeletal and cardiac myopathy and sudden cardiac death. Results We report on a 7-year-old boy diagnosed with primary carnitine deficiency 2 years after successful heart transplantation thanks his younger sister’s having been identified via expanded newborn screening during a pilot study evaluating an extension of the German newborn screening panel. Conclusion As L-carnitine supplementation can prevent and mostly reverse clinical symptoms of primary carnitine deficiency, all patients with cardiomyopathy should be investigated for primary carnitine deficiency even if newborn screening results were unremarkable.
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Affiliation(s)
- Sarah C Grünert
- Department of General Paediatrics, Adolescent Medicine and Neonatology, Medical Centre-University of Freiburg, Faculty of Medicine, Mathildenstraße 1, 79106, Freiburg, Germany.
| | - Sara Tucci
- Department of General Paediatrics, Adolescent Medicine and Neonatology, Medical Centre-University of Freiburg, Faculty of Medicine, Mathildenstraße 1, 79106, Freiburg, Germany
| | - Anke Schumann
- Department of General Paediatrics, Adolescent Medicine and Neonatology, Medical Centre-University of Freiburg, Faculty of Medicine, Mathildenstraße 1, 79106, Freiburg, Germany
| | - Meike Schwendt
- Department of Congenital Heart Disease and Paediatric Cardiology, University Heart Centre Freiburg - Bad Krozingen, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Gwendolyn Gramer
- University Hospital Heidelberg, Centre for Paediatric and Adolescent Medicine, Division of Neuropediatrics and Metabolic Medicine, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany
| | - Georg F Hoffmann
- University Hospital Heidelberg, Centre for Paediatric and Adolescent Medicine, Division of Neuropediatrics and Metabolic Medicine, Im Neuenheimer Feld 430, 69120, Heidelberg, Germany
| | - Michelle Erbel
- Institute of Pathology, Medical Centre-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Brigitte Stiller
- Department of Congenital Heart Disease and Paediatric Cardiology, University Heart Centre Freiburg - Bad Krozingen, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Ute Spiekerkoetter
- Department of General Paediatrics, Adolescent Medicine and Neonatology, Medical Centre-University of Freiburg, Faculty of Medicine, Mathildenstraße 1, 79106, Freiburg, Germany
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18
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Salomon JJ, Gausterer JC, Selo MA, Hosoya KI, Huwer H, Schneider-Daum N, Lehr CM, Ehrhardt C. OCTN2-Mediated Acetyl-l-Carnitine Transport in Human Pulmonary Epithelial Cells In Vitro. Pharmaceutics 2019; 11:E396. [PMID: 31394757 DOI: 10.3390/pharmaceutics11080396] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/31/2019] [Accepted: 08/06/2019] [Indexed: 12/24/2022] Open
Abstract
The carnitine transporter OCTN2 is associated with asthma and other inflammatory diseases. The aims of this work were (i) to determine carnitine uptake into freshly isolated human alveolar type I (ATI)-like epithelial cells in primary culture, (ii) to compare the kinetics of carnitine uptake between respiratory epithelial in vitro cell models, and (iii) to establish whether any cell line was a suitable model for studies of carnitine transport at the air-blood barrier. Levels of time-dependent [3H]-acetyl-l-carnitine uptake were similar in ATI-like, NCl-H441, and Calu-3 epithelial cells, whereas uptake into A549 cells was ~5 times higher. Uptake inhibition was more pronounced by OCTN2 modulators, such as l-Carnitine and verapamil, in ATI-like primary epithelial cells compared to NCl-H441 and Calu-3 epithelial cells. Our findings suggest that OCTN2 is involved in the cellular uptake of acetyl-l-carnitine at the alveolar epithelium and that none of the tested cell lines are optimal surrogates for primary cells.
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19
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Kou L, Sun R, Ganapathy V, Yao Q, Chen R. Recent advances in drug delivery via the organic cation/carnitine transporter 2 ( OCTN2/SLC22A5). Expert Opin Ther Targets 2018; 22:715-726. [PMID: 30016594 DOI: 10.1080/14728222.2018.1502273] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Transporters in the plasma membrane have been exploited successfully for the delivery of drugs in the form of prodrugs and nanoparticles. Organic cation/carnitine transporter 2 (OCTN2, SLC22A5) has emerged as a viable target for drug delivery. OCTN2 is a Na+-dependent high-affinity transporter for L-carnitine and a Na+-independent transporter for organic cations. OCTN2 is expressed in the blood-brain barrier, heart, liver, kidney, intestinal tract and placenta and plays an essential role in L-carnitine homeostasis in the body. Areas covered: In recent years, several studies have been reported in the literature describing the utility of OCTN2 to enhance the delivery of drugs, prodrugs and nanoparticles. Here we summarize the salient features of OCTN2 in terms of its role in the cellular uptake of its physiological substrate L-carnitine in physiological and pathological context; the structural requirements for recognition and the recent advances in OCTN2-targeted drug delivery systems, including prodrugs and nanoparticles, are discussed. Expert opinion: This transporter has great potential to be utilized as a target for drug delivery to improve oral absorption of drugs in the intestinal tract. It also has potential to facilitate the transfer of drugs across the biological barriers such as the blood-brain barrier, blood-retinal barrier, and maternal-fetal barrier.
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Affiliation(s)
- Longfa Kou
- a Department of Pharmacy , The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Rui Sun
- a Department of Pharmacy , The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Vadivel Ganapathy
- a Department of Pharmacy , The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China.,b Department of Cell Biology and Biochemistry , School of Medicine, Texas Tech University Health Sciences Center , Lubbock , TX , USA
| | - Qing Yao
- c School of Pharmaceutical Sciences , Wenzhou Medical University , Wenzhou , China
| | - Ruijie Chen
- a Department of Pharmacy , The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
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20
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Alghamdi A, Almalki H, Shawli A, Waggass R, Hakami F. A case of atypical systemic primary carnitine deficiency in Saudi Arabia. Pediatr Rep 2018; 10:7705. [PMID: 30069296 PMCID: PMC6050471 DOI: 10.4081/pr.2018.7705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 06/24/2018] [Indexed: 11/23/2022] Open
Abstract
Systemic primary carnitine deficiency (SPCD) is an autosomal recessive inborn error of fatty acid metabolism caused by a defect in the transporter responsible for moving carnitine across plasma membrane. The clinical features of SPCD vary widely based on the age of onset and organs involved. During infancy, patients might show episodes of hypoketotic hypoglycemia, hepatomegaly, elevated transaminases, and hyperammonemia. Skeletal myopathy, elevated creatine kinase, and cardiomyopathy are the main manifestations in children with SPCD, while in adults, the disorder is usually manifested as cardiomyopathy, arrhythmias, or fatigability. Here, we report a 5-year-old boy with SPCD that presented as dilated cardiomyopathy with atypical features, such as anemia, respiratory distress, and proximal muscle weakness. This report supports considering carnitine deficiency treatment in the work-up of unexplained pediatric dilated cardiomyopathy.
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Affiliation(s)
- Abdulrahman Alghamdi
- King Abdullah International Medical Research Center
- King Saud bin Abdulaziz University for Health Sciences
| | - Hani Almalki
- King Abdullah International Medical Research Center
- King Saud bin Abdulaziz University for Health Sciences
| | - Aiman Shawli
- King Abdullah International Medical Research Center
- King Saud bin Abdulaziz University for Health Sciences
- Department of Pediatrics
| | - Rahaf Waggass
- King Abdullah International Medical Research Center
- King Saud bin Abdulaziz University for Health Sciences
- King Faisal Cardiac Center
| | - Fahad Hakami
- King Abdullah International Medical Research Center
- King Saud bin Abdulaziz University for Health Sciences
- Molecular Medicine Section, Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City-WR, Jeddah, Saudi Arabia
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21
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Berg T, Hegelund-Myrbäck T, Öckinger J, Zhou XH, Brännström M, Hagemann-Jensen M, Werkström V, Seidegård J, Grunewald J, Nord M, Gustavsson L. Expression of MATE1, P-gp, OCTN1 and OCTN2, in epithelial and immune cells in the lung of COPD and healthy individuals. Respir Res 2018; 19:68. [PMID: 29678179 PMCID: PMC5910606 DOI: 10.1186/s12931-018-0760-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 03/27/2018] [Indexed: 02/03/2023] Open
Abstract
Background Several inhaled drugs are dependent on organic cation transporters to cross cell membranes. To further evaluate their potential to impact on inhaled drug disposition, the localization of MATE1, P-gp, OCTN1 and OCTN2 were investigated in human lung. Methods Transporter proteins were analysed by immunohistochemistry in lung tissue from healthy subjects and COPD patients. Transporter mRNA was analysed by qPCR in lung tissue and in bronchoalveolar lavage (BAL) cells from smokers and non-smokers. Results We demonstrate for the first time MATE1 protein expression in the lung with localization to the apical side of bronchial and bronchiolar epithelial cells. Interestingly, MATE1 was strongly expressed in alveolar macrophages as demonstrated both in lung tissue and in BAL cells, and in inflammatory cells including CD3 positive T cells. P-gp, OCTN1 and OCTN2 were also expressed in the alveolar epithelial cells and in inflammatory cells including alveolar macrophages. In BAL cells from smokers, MATE1 and P-gp mRNA expression was significantly lower compared to cells from non-smokers whereas no difference was observed between COPD patients and healthy subjects. THP-1 cells were evaluated as a model for alveolar macrophages but did not reflect the transporter expression observed in BAL cells. Conclusions We conclude that MATE1, P-gp, OCTN1 and OCTN2 are expressed in pulmonary lung epithelium, in alveolar macrophages and in other inflammatory cells. This is important to consider in the development of drugs treating pulmonary disease as the transporters may impact drug disposition in the lung and consequently affect pharmacological efficacy and toxicity. Electronic supplementary material The online version of this article (10.1186/s12931-018-0760-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tove Berg
- Respiratory Medicine Unit, Department of Medicine Solna and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Tove Hegelund-Myrbäck
- Quantitative Clinical Pharmacology, Early Clinical Development, IMED Biotech Unit, AstraZeneca R&D, Gothenburg, Sweden.
| | - Johan Öckinger
- Respiratory Medicine Unit, Department of Medicine Solna and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Xiao-Hong Zhou
- Respiratory, Inflammation and Autoimmunity, IMED Biotech Unit, AstraZeneca R&D, Gothenburg, Sweden
| | - Marie Brännström
- Respiratory, Inflammation and Autoimmunity, IMED Biotech Unit, AstraZeneca R&D, Gothenburg, Sweden
| | - Michael Hagemann-Jensen
- Respiratory Medicine Unit, Department of Medicine Solna and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Viktoria Werkström
- Respiratory GMed, Global Medicines Development, AstraZeneca R&D, Gothenburg, Sweden
| | - Janeric Seidegård
- Respiratory, Inflammation and Autoimmunity, IMED Biotech Unit, AstraZeneca R&D, Gothenburg, Sweden
| | - Johan Grunewald
- Respiratory Medicine Unit, Department of Medicine Solna and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Nord
- Respiratory Medicine Unit, Department of Medicine Solna and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Global Patient Safety, Global Medicines Development, AstraZeneca R&D, Gothenburg, Sweden
| | - Lena Gustavsson
- Department of Drug Metabolism, H. Lundbeck A/S, Ottiliavej 9, 2500, Valby, Denmark
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22
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Kou L, Yao Q, Sivaprakasam S, Luo Q, Sun Y, Fu Q, He Z, Sun J, Ganapathy V. Dual targeting of l-carnitine-conjugated nanoparticles to OCTN2 and ATB 0,+ to deliver chemotherapeutic agents for colon cancer therapy. Drug Deliv 2017; 24:1338-1349. [PMID: 28911246 PMCID: PMC8241000 DOI: 10.1080/10717544.2017.1377316] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
l-Carnitine, obligatory for oxidation of fatty acids, is transported into cells by the Na+-coupled transporter OCTN2 and the Na+/Cl–-coupled transporter ATB0,+. Here we investigated the potential of L-carnitine-conjugated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (LC-PLGA NPs) to deliver chemotherapeutic drugs into cancer cells by targeting the nanoparticles to both OCTN2 and ATB0,+. The cellular uptake of LC-PLGA NPs in the breast cancer cell line MCF7 and the colon cancer cell line Caco-2 was increased compared to unmodified nanoparticles, but decreased in the absence of co-transporting ions (Na+ and/or Cl–) or in the presence of competitive substrates for the two transporters. Studies with fluorescently labeled nanoparticles showed their colocalization with both OCTN2 and ATB0,+, confirming the involvement of both transporters in the cellular uptake of LC-PLGA NPs. As the expression levels of OCTN2 and ATB0,+ are higher in colon cancer cells than in normal colon cells, LC-PLGA NPs can be used to deliver chemotherapeutic drugs selectively into cancer cells for colon cancer therapy. With 5-fluorouracil-loaded LC-PLGA NPs, we were able to demonstrate significant increases in the uptake efficiency and cytotoxicity in colon cancer cells that were positive for OCTN2 and ATB0,+. In a 3D spheroid model of tumor growth, LC-PLGA NPs showed increased uptake and enhanced antitumor efficacy. These findings indicate that dual-targeting LC-PLGA NPs to OCTN2 and ATB0,+ has great potential to deliver chemotherapeutic drugs for colon cancer therapy. Dual targeting LC-PLGA NPs to OCTN2 and ATB0,+ can selectively deliver chemotherapeutics to colon cancer cells where both transporters are overexpressed, preventing targeting to normal cells and thus avoiding off-target side effects.
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Affiliation(s)
- Longfa Kou
- a Municipal Key Laboratory of Biopharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China.,b Department of Cell Biology and Biochemistry , Texas Tech University Health Sciences Center , Lubbock , TX , USA
| | - Qing Yao
- a Municipal Key Laboratory of Biopharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China
| | - Sathish Sivaprakasam
- b Department of Cell Biology and Biochemistry , Texas Tech University Health Sciences Center , Lubbock , TX , USA
| | - Qiuhua Luo
- a Municipal Key Laboratory of Biopharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China
| | - Yinghua Sun
- a Municipal Key Laboratory of Biopharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China
| | - Qiang Fu
- a Municipal Key Laboratory of Biopharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China
| | - Zhonggui He
- c Department of Pharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China
| | - Jin Sun
- a Municipal Key Laboratory of Biopharmaceutics , Wuya College of Innovation, Shenyang Pharmaceutical University , Shenyang , China
| | - Vadivel Ganapathy
- b Department of Cell Biology and Biochemistry , Texas Tech University Health Sciences Center , Lubbock , TX , USA
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23
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Kou L, Hou Y, Yao Q, Guo W, Wang G, Wang M, Fu Q, He Z, Ganapathy V, Sun J. L-Carnitine-conjugated nanoparticles to promote permeation across blood-brain barrier and to target glioma cells for drug delivery via the novel organic cation/carnitine transporter OCTN2. Artif Cells Nanomed Biotechnol 2017; 46:1605-1616. [PMID: 28974108 DOI: 10.1080/21691401.2017.1384385] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Overcoming blood-brain barrier (BBB) and targeting tumor cells are two key steps for glioma chemotherapy. By taking advantage of the specific expression of Na+-coupled carnitine transporter 2 (OCTN2) on both brain capillary endothelial cells and glioma cells, l-carnitine conjugated poly(lactic-co-glycolic acid) nanoparticles (LC-PLGA NPs) were prepared to enable enhanced BBB permeation and glioma-cell targeting. Conjugation of l-carnitine significantly enhanced the uptake of PLGA nanoparticles in the BBB endothelial cell line hCMEC/D3 and the glioma cell line T98G. The uptake was dependent on Na+ and inhibited by the excessive free l-carnitine, suggesting involvement of OCTN2 in the process. In vivo mouse studies showed that LC-PLGA NPs resulted in high accumulation in the brain as indicated by the biodistribution and imaging assays. Furthermore, compared to Taxol and paclitaxel-loaded unmodified PLGA NPs, the drug-loaded LC-PLGA NPs showed improved anti-glioma efficacy in both 2D-cell and 3D-spheroid models. The PEG spacer length of the ligand attached to the nanoparticles was optimized, and the formulation with PEG1000 (LC-1000-PLGA NPs) showed the maximum targeting efficiency. We conclude that l-carnitine-mediated cellular recognition and internalization via OCTN2 significantly facilitate the transcytosis of nanoparticles across BBB and the uptake of nanoparticles in glioma cells, resulting in improved anti-glioma efficacy.
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Affiliation(s)
- Longfa Kou
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China.,b Department of Cell Biology and Biochemistry , Texas Tech University Health Sciences Center , Lubbock , TX , USA
| | - Yanxian Hou
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Qing Yao
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Weiling Guo
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Gang Wang
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Menglin Wang
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Qiang Fu
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Zhonggui He
- c Department of Pharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
| | - Vadivel Ganapathy
- b Department of Cell Biology and Biochemistry , Texas Tech University Health Sciences Center , Lubbock , TX , USA
| | - Jin Sun
- a Municipal Key Laboratory of Biopharmaceutics, Wuya College of Innovation , Shenyang Pharmaceutical University , Shenyang , China
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24
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Frigeni M, Balakrishnan B, Yin X, Calderon FRO, Mao R, Pasquali M, Longo N. Functional and molecular studies in primary carnitine deficiency. Hum Mutat 2017; 38:1684-1699. [PMID: 28841266 DOI: 10.1002/humu.23315] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/13/2017] [Accepted: 08/17/2017] [Indexed: 12/30/2022]
Abstract
Primary carnitine deficiency is caused by a defect in the OCTN2 carnitine transporter encoded by the SLC22A5 gene. It can cause hypoketotic hypoglycemia or cardiomyopathy in children, and sudden death in children and adults. Fibroblasts from affected patients have reduced carnitine transport. We evaluated carnitine transport in fibroblasts from 358 subjects referred for possible carnitine deficiency. Carnitine transport was reduced to 20% or less of normal in fibroblasts of 140 out of 358 subjects. Sequencing of the 10 exons and flanking regions of the SLC22A5 gene in 95 out of 140 subjects identified causative variants in 84% of the alleles. The missense variants identified in our patients and others previously reported (n = 92) were expressed in CHO cells. Carnitine transport was impaired by 73 out of 92 variants expressed. Prediction algorithms (Polyphen-2, SIFT) correctly predicted the functional effects of expressed variants in about 80% of cases. These results indicate that mutations in the coding region of the SLC22A5 gene cannot be identified in about 16% of the alleles causing primary carnitine deficiency. Prediction algorithms failed to determine the functional effects of amino acid substitutions in this transmembrane protein in about 20% of cases. Therefore, functional studies in fibroblasts remain the best strategy to confirm or exclude a diagnosis of primary carnitine deficiency.
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Affiliation(s)
- Marta Frigeni
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, Utah
| | - Bijina Balakrishnan
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, Utah
| | - Xue Yin
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, Utah
| | - Fernanda R O Calderon
- ARUP Institute for Clinical and Experimental Pathology®, ARUP Laboratories, Salt Lake City, Utah.,Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Rong Mao
- ARUP Institute for Clinical and Experimental Pathology®, ARUP Laboratories, Salt Lake City, Utah.,Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Marzia Pasquali
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, Utah.,ARUP Institute for Clinical and Experimental Pathology®, ARUP Laboratories, Salt Lake City, Utah.,Department of Pathology, University of Utah, Salt Lake City, Utah
| | - Nicola Longo
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, Utah.,ARUP Institute for Clinical and Experimental Pathology®, ARUP Laboratories, Salt Lake City, Utah.,Department of Pathology, University of Utah, Salt Lake City, Utah
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25
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Kou L, Yao Q, Sun M, Wu C, Wang J, Luo Q, Wang G, Du Y, Fu Q, Wang J, He Z, Ganapathy V, Sun J. Cotransporting Ion is a Trigger for Cellular Endocytosis of Transporter-Targeting Nanoparticles: A Case Study of High-Efficiency SLC22A5 ( OCTN2)-Mediated Carnitine-Conjugated Nanoparticles for Oral Delivery of Therapeutic Drugs. Adv Healthc Mater 2017; 6. [PMID: 28661032 DOI: 10.1002/adhm.201700165] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/21/2017] [Indexed: 01/16/2023]
Abstract
OCTN2 (SLC22A5) is a Na+ -coupled absorption transporter for l-carnitine in small intestine. This study tests the potential of this transporter for oral delivery of therapeutic drugs encapsulated in l-carnitine-conjugated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (LC-PLGA NPs) and discloses the molecular mechanism for cellular endocytosis of transporter-targeting nanoparticles. Conjugation of l-carnitine to a surface of PLGA-NPs enhances the cellular uptake and intestinal absorption of encapsulated drug. In both cases, the uptake process is dependent on cotransporting ion Na+ . Computational OCTN2 docking analysis shows that the presence of Na+ is important for the formation of the energetically stable intermediate complex of transporter-Na+ -LC-PLGA NPs, which is also the first step in cellular endocytosis of nanoparticles. The transporter-mediated intestinal absorption of LC-PLGA NPs occurs via endocytosis/transcytosis rather than via the traditional transmembrane transport. The portal blood versus the lymphatic route is evaluated by the plasma appearance of the drug in the control and lymph duct-ligated rats. Absorption via the lymphatic system is the predominant route in the oral delivery of the NPs. In summary, LC-PLGA NPs can effectively target OCTN2 on the enterocytes for enhancing oral delivery of drugs and the critical role of cotransporting ions should be noticed in designing transporter-targeting nanoparticles.
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Affiliation(s)
- Longfa Kou
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
- Department of Cell Biology and Biochemistry; Texas Tech University Health Sciences Center; Lubbock TX 79430 USA
| | - Qing Yao
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Mengchi Sun
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Chunnuan Wu
- Tianjin Medical University Cancer Institute & Hospital; Tianjin 300060 China
| | - Jia Wang
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Qiuhua Luo
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Gang Wang
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Yuqian Du
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Qiang Fu
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
| | - Jian Wang
- Key Laboratory of Structure-Based Drug Design and Discovery; Shenyang Pharmaceutical University; Ministry of Education; Shenyang 110016 China
| | - Zhonggui He
- Department of Pharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; Shenyang 110016 China
| | - Vadivel Ganapathy
- Department of Cell Biology and Biochemistry; Texas Tech University Health Sciences Center; Lubbock TX 79430 USA
| | - Jin Sun
- Municipal Key Laboratory of Biopharmaceutics; School of Pharmacy; Shenyang Pharmaceutical University; No. 103 Wenhua Road Shenyang 110016 China
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George B, You D, Joy MS, Aleksunes LM. Xenobiotic transporters and kidney injury. Adv Drug Deliv Rev 2017; 116:73-91. [PMID: 28111348 DOI: 10.1016/j.addr.2017.01.005] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 01/02/2017] [Accepted: 01/13/2017] [Indexed: 02/07/2023]
Abstract
Renal proximal tubules are targets for toxicity due in part to the expression of transporters that mediate the secretion and reabsorption of xenobiotics. Alterations in transporter expression and/or function can enhance the accumulation of toxicants and sensitize the kidneys to injury. This can be observed when xenobiotic uptake by carrier proteins is increased or efflux of toxicants and their metabolites is reduced. Nephrotoxic chemicals include environmental contaminants (halogenated hydrocarbon solvents, the herbicide paraquat, the fungal toxin ochratoxin, and heavy metals) as well as pharmaceuticals (certain beta-lactam antibiotics, antiviral drugs, and chemotherapeutic drugs). This review explores the mechanisms by which transporters mediate the entry and exit of toxicants from renal tubule cells and influence the degree of kidney injury. Delineating how transport proteins regulate the renal accumulation of toxicants is critical for understanding the likelihood of nephrotoxicity resulting from competition for excretion or genetic polymorphisms that affect transporter function.
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Szabó K, Nagy Z, Juhász V, Zolnerciks JK, Csorba A, Tímár Z, Molnár É, Pádár P, Johnson W, Beéry E, Krajcsi P. Species specificity profiling of rat and human organic cation/carnitine transporter Slc22a5/SLC22A5 ( Octn2/OCTN2). Drug Metab Pharmacokinet 2016; 32:165-171. [PMID: 28365301 DOI: 10.1016/j.dmpk.2016.08.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/25/2016] [Accepted: 08/18/2016] [Indexed: 01/09/2023]
Abstract
The purpose of this study was to characterize the uptake of carnitine, the physiological substrate, and the uptake of 3-(2,2,2-trimethylhydrazinium)propionate, a consensus substrate by rat Octn2 and human OCTN2 transporters as well as to characterize drug-mediated inhibition of l-carnitine uptake by the rat and human orthologs overexpressed in CHO-K1 cells. l-carnitine and 3-(2,2,2-trimethylhydrazinium)propionate were found to be a lower affinity substrate for rat Octn2 (KM = 32.66 ± 5.11 μM and 23.62 ± 4.99 μM respectively) than for human OCTN2 (KM = 3.08 ± 0.74 μM and 7.98 ± 0.63 μM). The intrinsic clearance (CLint) value for carnitine was higher for the human than for the rat transporter (22.82 ± 5.57 ml/min*mg vs 4.008 ± 0.675 ml/min*mg). For 3-(2,2,2-trimethylhydrazinium)propionate, in contrast, the CLint value for rat Octn2 was higher than for human OCTN2 (323.9 ± 72.8 ml/min*mg vs 65.11 ± 5.33 ml/min*mg). Furthermore, many pharmacologically important drugs were shown to affect l-carnitine transport by Octn2/OCTN2. The correlation between the IC50 datasets for the rat and human transporter resulted in an r value of 0.47 (p > 0.05). However, the greatest difference was less than seven-fold and 13 of 15 compounds yielded a difference less than 3-fold. Thus, the transporters from these two species showed an overlapping but somewhat different substrate and inhibitor specificity.
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Affiliation(s)
- Kitti Szabó
- SOLVO Biotechnology, 2 Gyár utca, Budaörs 2040, Hungary; SOLVO Biotechnology, 52 Közép fasor, Szeged 6726, Hungary.
| | - Zoltán Nagy
- SOLVO Biotechnology, 2 Gyár utca, Budaörs 2040, Hungary.
| | | | | | - Attila Csorba
- SOLVO Biotechnology, 52 Közép fasor, Szeged 6726, Hungary.
| | - Zoltán Tímár
- SOLVO Biotechnology, 52 Közép fasor, Szeged 6726, Hungary.
| | - Éva Molnár
- SOLVO Biotechnology, 52 Közép fasor, Szeged 6726, Hungary.
| | - Petra Pádár
- SOLVO Biotechnology, 52 Közép fasor, Szeged 6726, Hungary.
| | | | - Erzsébet Beéry
- SOLVO Biotechnology, 2 Gyár utca, Budaörs 2040, Hungary.
| | - Péter Krajcsi
- SOLVO Biotechnology, 2 Gyár utca, Budaörs 2040, Hungary.
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Luo J, Qu J, Yang R, Ge MX, Mei Y, Zhou BT, Qu Q. Phytochemicals Mediate the Expression and Activity of OCTN2 as Activators of the PPARγ/RXRα Pathway. Front Pharmacol 2016; 7:189. [PMID: 27445823 PMCID: PMC4925669 DOI: 10.3389/fphar.2016.00189] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 06/14/2016] [Indexed: 12/20/2022] Open
Abstract
Many phytochemicals exert activities as agonists of peroxisome proliferator-activated receptor gamma (PPARγ). This study aims to investigate whether phytochemicals are agonists of the PPARγ/RXRα pathway and modulate the target gene OCTN2. In this study, a luciferase reporter gene system was used to screen novel OCTN2 activators from 39 phytochemicals. Kaempferol, curcumin, and puerarin were found to show the significant PPRE-mediated luciferase activities (>150%) at 20 μM and showed a dose-dependent manner. Phytochemicals also elevated the mRNA and protein expression of OCTN2 in a dose-dependent fashion in colorectal cancer SW480 cells. These induction effects were gradually inhibited by PPARγ antagonist GW9662 in the luciferase reporter gene system and in SW480 cells. Moreover, the results of cell viability assay imply that three phytochemicals probably induce OCTN2 expression leading to the enhanced uptake of its substrate, oxaliplatin, thereby making cells more sensitive to oxaliplatin. The molecular docking study showed the possible binding sites of phytochemicals in PPARγ protein, and all of the docked phytochemicals fitted the same active pocket in PPARγ as troglitazone. All three phytochemicals exhibited hydrogen bonds between their polar moieties and the amino acid residues. Thus, we identified three phytochemicals as PPARγ ligands, which potentiated the expression and activity of OCTN2.
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Affiliation(s)
- Jian Luo
- Department of Pharmacy, Xiangya Hospital, Central South University Changsha, China
| | - Jian Qu
- Department of Pharmacy, Second Xiangya Hospital and Institute of Clinical Pharmacy, Central South University Changsha, China
| | - Rui Yang
- Department of Pharmacy, Xiangya Hospital, Central South University Changsha, China
| | - Meng-Xue Ge
- Institute of Clinical Pharmacology, Xiangya Hospital, Central South University Changsha, China
| | - Yin Mei
- Institute of Clinical Pharmacology, Xiangya Hospital, Central South University Changsha, China
| | - Bo-Ting Zhou
- Department of Pharmacy, Xiangya Hospital, Central South University Changsha, China
| | - Qiang Qu
- Department of Pharmacy, Xiangya Hospital, Central South University Changsha, China
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Frigeni M, Iacobazzi F, Yin X, Longo N. Wide tolerance to amino acids substitutions in the OCTN1 ergothioneine transporter. Biochim Biophys Acta Gen Subj 2016; 1860:1334-42. [PMID: 26994919 DOI: 10.1016/j.bbagen.2016.03.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 02/24/2016] [Accepted: 03/15/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND Organic cation transporters transfer solutes with a positive charge across the plasma membrane. The novel organic cation transporter 1 (OCTN1) and 2 (OCTN2) transport ergothioneine and carnitine, respectively. Mutations in the SLC22A5 gene encoding OCTN2 cause primary carnitine deficiency, a recessive disorders resulting in low carnitine levels and defective fatty acid oxidation. Variations in the SLC22A4 gene encoding OCTN1 are associated with rheumatoid arthritis and Crohn disease. METHODS Here we evaluate the functional properties of the OCTN1 transporter using chimeric transporters constructed by fusing different portion of the OCTN1 and OCTN2 cDNAs. Their relative abundance and subcellular distribution was evaluated through western blot analysis and confocal microscopy. RESULTS Substitutions of the C-terminal portion of OCTN1 with the correspondent residues of OCTN2 generated chimeric OCTN transporters more active than wild-type OCTN1 in transporting ergothioneine. Additional single amino acid substitutions introduced in chimeric OCTN transporters further increased ergothioneine transport activity. Kinetic analysis indicated that increased transport activity was due to an increased V(max), with modest changes in K(m) toward ergothioneine. CONCLUSIONS Our results indicate that the OCTN1 transporter is tolerant to extensive amino acid substitutions. This is in sharp contrast to the OCTN2 carnitine transporter that has been selected for high functional activity through evolution, with almost all substitutions reducing carnitine transport activity. GENERAL SIGNIFICANCE The widespread tolerance of OCTN1 to amino acid substitutions suggests that the corresponding SLC22A4 gene may have derived from a recent duplication of the SLC22A5 gene and might not yet have a defined physiological role.
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Affiliation(s)
- Marta Frigeni
- Division of Medical Genetics, Departments of Pediatrics and Pathology, University of Utah, Salt Lake City, UT 84108, United States
| | - Francesco Iacobazzi
- Division of Medical Genetics, Departments of Pediatrics and Pathology, University of Utah, Salt Lake City, UT 84108, United States; Department of Basic Medical Sciences, University of Bari, Policlinico, I-70124 Bari, Italy
| | - Xue Yin
- Division of Medical Genetics, Departments of Pediatrics and Pathology, University of Utah, Salt Lake City, UT 84108, United States
| | - Nicola Longo
- Division of Medical Genetics, Departments of Pediatrics and Pathology, University of Utah, Salt Lake City, UT 84108, United States.
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Longo N, Frigeni M, Pasquali M. Carnitine transport and fatty acid oxidation. Biochim Biophys Acta 2016; 1863:2422-35. [PMID: 26828774 DOI: 10.1016/j.bbamcr.2016.01.023] [Citation(s) in RCA: 443] [Impact Index Per Article: 55.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 12/14/2022]
Abstract
Carnitine is essential for the transfer of long-chain fatty acids across the inner mitochondrial membrane for subsequent β-oxidation. It can be synthesized by the body or assumed with the diet from meat and dairy products. Defects in carnitine biosynthesis do not routinely result in low plasma carnitine levels. Carnitine is accumulated by the cells and retained by kidneys using OCTN2, a high affinity organic cation transporter specific for carnitine. Defects in the OCTN2 carnitine transporter results in autosomal recessive primary carnitine deficiency characterized by decreased intracellular carnitine accumulation, increased losses of carnitine in the urine, and low serum carnitine levels. Patients can present early in life with hypoketotic hypoglycemia and hepatic encephalopathy, or later in life with skeletal and cardiac myopathy or sudden death from cardiac arrhythmia, usually triggered by fasting or catabolic state. This disease responds to oral carnitine that, in pharmacological doses, enters cells using the amino acid transporter B(0,+). Primary carnitine deficiency can be suspected from the clinical presentation or identified by low levels of free carnitine (C0) in the newborn screening. Some adult patients have been diagnosed following the birth of an unaffected child with very low carnitine levels in the newborn screening. The diagnosis is confirmed by measuring low carnitine uptake in the patients' fibroblasts or by DNA sequencing of the SLC22A5 gene encoding the OCTN2 carnitine transporter. Some mutations are specific for certain ethnic backgrounds, but the majority are private and identified only in individual families. Although the genotype usually does not correlate with metabolic or cardiac involvement in primary carnitine deficiency, patients presenting as adults tend to have at least one missense mutation retaining residual activity. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
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Affiliation(s)
- Nicola Longo
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA; Department of Pathology, University of Utah, and ARUP Laboratories, 500 Chipeta Way, Salt Lake City, UT, USA.
| | - Marta Frigeni
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Marzia Pasquali
- Department of Pathology, University of Utah, and ARUP Laboratories, 500 Chipeta Way, Salt Lake City, UT, USA
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Ingoglia F, Visigalli R, Rotoli BM, Barilli A, Riccardi B, Puccini P, Dall'Asta V. Functional activity of L-carnitine transporters in human airway epithelial cells. Biochim Biophys Acta 2015; 1858:210-9. [PMID: 26607009 DOI: 10.1016/j.bbamem.2015.11.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/21/2015] [Accepted: 11/18/2015] [Indexed: 12/30/2022]
Abstract
Carnitine plays a physiologically important role in the β-oxidation of fatty acids, facilitating the transport of long-chain fatty acids across the inner mitochondrial membrane. Distribution of carnitine within the body tissues is mainly performed by novel organic cation transporter (OCTN) family, including the isoforms OCTN1 (SLC22A4) and OCTN2 (SLC22A5) expressed in human. We performed here a characterization of carnitine transport in human airway epithelial cells A549, Calu-3, NCl-H441, and BEAS-2B, by means of an integrated approach combining data of mRNA/protein expression with the kinetic and inhibition analyses of L-[(3)H]carnitine transport. Carnitine uptake was strictly Na(+)-dependent in all cell models. In A549 and BEAS-2B cells, carnitine uptake was mediated by one high-affinity component (Km<2 μM) identifiable with OCTN2. In both these cell models, indeed, carnitine uptake was maximally inhibited by betaine and strongly reduced by SLC22A5/OCTN2 silencing. Conversely, Calu-3 and NCl-H441 exhibited both a high (Km~20 μM) and a low affinity (Km>1 mM) transport component. While the high affinity component is identifiable with OCTN2, the low affinity uptake is mediated by ATB(0,+), a Na(+), and Cl(-)-coupled transport system for neutral and cationic amino acids, as demonstrated by the inhibition by leucine and arginine, as well as by SLC6A14/ATB(0,+) silencing. The presence of this transporter leads to a massive accumulation of carnitine inside the cells and may be of peculiar relevance in pathologic conditions of carnitine deficiency, such as those associated to OCTN2 defects.
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Affiliation(s)
- Filippo Ingoglia
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Rossana Visigalli
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Bianca Maria Rotoli
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Amelia Barilli
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy
| | - Benedetta Riccardi
- Preclinical Pharmacokinetics, Biochemistry & Metabolism Dept., Chiesi Farmaceutici, Largo F. Belloli 11/A, 43122 Parma, Italy
| | - Paola Puccini
- Preclinical Pharmacokinetics, Biochemistry & Metabolism Dept., Chiesi Farmaceutici, Largo F. Belloli 11/A, 43122 Parma, Italy
| | - Valeria Dall'Asta
- Dept. of Biomedical, Biotechnological and Translational Sciences (SBiBiT), University of Parma, Via Volturno 39, 43125 Parma, Italy.
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Droździk M, Oronowicz K, Piasecka M, Kazienko A, Rosiak A, Gill K, Dziedziejko V, Safranow K, Kurzawa R, Kurzawski M. Organic cation/carnitine transporter OCTN2 (SLC22A5) -207C>G (rs2631367) polymorphism is not associated with male infertility. Reprod Biol 2015; 15:178-83. [PMID: 26370461 DOI: 10.1016/j.repbio.2015.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 05/05/2015] [Accepted: 06/06/2015] [Indexed: 10/23/2022]
Abstract
Carnitine is an important factor in the initiation of progressive sperm motility and end stage of sperm maturation. The compound is transported by an organic cation/carnitine transporter (OCTN2), which is expressed in the male reproductive system. OCTN2 is encoded by SLC22A5 gene with proven -207C>G functional polymorphism. The aim of the case-control study was to investigate a potential association between the -207C>G SLC22A5 polymorphism and male infertility. The -207C>G SLC22A5 polymorphism was determined by means of TaqMan assay in 206 infertile Caucasian males and 256 ethnically matched controls. Besides genotyping study, sperm mitochondrial function was assessed using NADH-dependent NBT assay. The distribution of SLC22A5 genotypes in infertile men was as follows: CC - 29.6%, CG - 53.9%, GG - 16.5% and in fertile men: CC - 32.0%, CG - 50.0%, GG - 18.0%, and was comparable in both evaluated groups. Likewise, the studied polymorphism did not affect sperm mitochondrial function. The results of the current study demonstrated that -207C>G polymorphism of the SLC22A5 gene is not associated with male infertility.
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Affiliation(s)
- Marek Droździk
- Department of Experimental and Clinical Pharmacology, Pomeranian Medical University, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
| | - Katarzyna Oronowicz
- Department of Obstetrics and Gynecology, County Hospital, Mączna 4, 70-780 Szczecin, Poland
| | - Malgorzata Piasecka
- Department of Histology and Developmental Biology, Pomeranian Medical University, Żołnierska 48, 71-210 Szczecin, Poland
| | - Anna Kazienko
- Department of Reproductive Medicine and Gynecology, Pomeranian Medical University, Siedlecka 2, Police, Poland
| | - Aleksandra Rosiak
- Department of Histology and Developmental Biology, Pomeranian Medical University, Żołnierska 48, 71-210 Szczecin, Poland; VitroLive Fertility Clinic, Kasprzaka 2A, 71-074 Szczecin, Poland
| | - Kamil Gill
- Department of Histology and Developmental Biology, Pomeranian Medical University, Żołnierska 48, 71-210 Szczecin, Poland
| | - Violetta Dziedziejko
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
| | - Krzysztof Safranow
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
| | - Rafał Kurzawa
- Department of Reproductive Medicine and Gynecology, Pomeranian Medical University, Siedlecka 2, Police, Poland; VitroLive Fertility Clinic, Kasprzaka 2A, 71-074 Szczecin, Poland
| | - Mateusz Kurzawski
- Department of Experimental and Clinical Pharmacology, Pomeranian Medical University, Powstańców Wlkp. 72, 70-111 Szczecin, Poland.
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Rasmussen J, Lund AM, Risom L, Wibrand F, Gislason H, Nielsen OW, Køber L, Duno M. Residual OCTN2 transporter activity, carnitine levels and symptoms correlate in patients with primary carnitine deficiency. Mol Genet Metab Rep 2014; 1:241-8. [PMID: 27896095 DOI: 10.1016/j.ymgmr.2014.04.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 04/25/2014] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The prevalence of primary carnitine deficiency (PCD) in the Faroe Islands is the highest reported in the world (1:300). Serious symptoms related to PCD, e.g. sudden death, have previously only been associated to the c.95A > G/c.95A > G genotype in the Faroe Islands. We report and characterize novel mutations associated with PCD in the Faroese population and report and compare free carnitine levels and OCTN2 transport activities measured in fibroblasts from PCD patients with different genotypes. METHODS Genetic analyses were used to identify novel mutations, and carnitine uptake analyses in cultured skin fibroblasts from selected patients were used to examine residual OCTN2 transporter activities of the various genotypes. RESULTS Four different mutations, including the unpublished c.131C > T (p.A44V), the novel splice mutation c.825-52G > A and a novel risk-haplotype (RH) were identified in the Faroese population. The two most prevalent genotypes were c.95A > G/RH (1:600) and c.95A > G/c.95A > G (1:1300). Patients homozygous for the c.95A > G mutation had both the significantly (p < 0.01) lowest mean free carnitine level at 2.03 (SD 0.66) μmol/L and lowest residual OCTN2 transporter activity (4% of normal). There was a significant positive correlation between free carnitine levels and residual OCTN2 transporter activities in PCD patients (R2 = 0.430, p < 0.01). CONCLUSION There was a significant positive correlation between carnitine levels and OCTN2 transporter activities. The c.95A > G/c.95A > G genotype had the significantly lowest mean free carnitine level and residual OCTN2 transporter activity.
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Bene J, Magyari L, Talián G, Komlósi K, Gasztonyi B, Tari B, Várkonyi A, Mózsik G, Melegh B. Prevalence of SLC22A4, SLC22A5 and CARD15 gene mutations in Hungarian pediatric patients with Crohn’s disease. World J Gastroenterol 2006; 12:5550-3. [PMID: 17006998 PMCID: PMC4088243 DOI: 10.3748/wjg.v12.i34.5550] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the frequency of the common NOD2/CARD15 susceptibility variants and two functional polymorphisms of OCTN cation transporter genes in Hungarian pediatric patients with Crohn’s disease (CD).
METHODS: A cohort of 19 unrelated pediatric and 55 unrelated adult patients with Crohn’s disease and 49 healthy controls were studied. Genotyping of the three common CD-associated CARD15 variants (Arg702Trp, Gly908Arg and 1007finsC changes) with the SLC22A4 1672C→T, and SLC22A5 -207G→C mutations was performed by direct sequencing of the specific regions of these genes.
RESULTS: At least one CARD15 mutation was present in 52.6% of the children and in 34.5% of the adults compared to 14.3% in controls. Surprisingly, strongly different mutation profile was detected in the pediatric versus adult patients. While the G908R and 1007finsC variants were 18.4% and 21.1% in the pediatric group, they were 1.82% and 11.8% in the adults, and were 1.02% and 3.06% in the controls, respectively. The R702W allele was increased approximately two-fold in the adult subjects, while in the pediatric group it was only approximately 64% of the controls (9.09% in the adults, 2.63% in pediatric patients, and 4.08% in the controls). No accumulation of the OCTN variants was observed in any patient group versus the controls.
CONCLUSION: The frequency of the NOD2/CARD15 susceptibility variants in the Hungarian pediatric CD population is high and the profile differs from the adult CD patients, whereas the results for SLC22A4 and SLC22A5 mutation screening do not confirm the assumption that the carriage of these genotypes means an obligatory susceptibility to CD.
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Affiliation(s)
- Judit Bene
- Department of Medical Genetics and Child Development, University of Pecs, H-7624 Pecs, Szigeti 12, Hungary
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