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Xiao M, Zheng L, Zhang X, Duan X, Hang T, Lu S, Liu S, Lin H. Renal-on-Chip Microfluidic Platform with a Force-Sensitive Resistor (ROC-FS) for Molecular Pathogenesis Analysis of Hydronephrosis. Anal Chem 2021; 94:748-757. [PMID: 34951537 DOI: 10.1021/acs.analchem.1c03155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydronephrosis is one of the most common diseases in urology. However, due to the difficulties in clinical trials and the lack of reliable in vitro platforms, the surgical indicators are not clear. Herein, the renal-on-chip with a force-sensitive resistor microfluidic platform was established to simulate the state of hydronephrosis. Cell counting kit-8 (CCK-8) and tight junction protein claudin-2 were detected on a renal-on-chip microfluidic platform with a force-sensitive resistor (ROC-FS). The results indicated that the ROC-FS had normal physiological functions and the cell viability on ROC-FS declined to around 40% after 48 h of hydronephrosis-simulated treatment. In addition, proteomics analysis of 15 clinical ureteropelvic junction obstruction (UPJO) samples showed that compared with normal children, a total of 50 common proteins were differentially expressed in UPJO children (P < 0.05, |log2fold change| ≥ 1). Metabolomic analysis of 39 clinical UPJO samples showed that a total of 241 metabolisms were dysregulated. Subsequent immunofluorescence and enzyme-linked immunosorbent assay (ELISA) analysis using ROC-FS were performed to identify the clinical multi-omics results for screening. All results pointed out that the TGF-β-related signaling pathways and arginine-related metabolism signaling pathways were dysregulated and α-SMA, AGT, and AGA might be the potential biomarkers of hydronephrosis. In addition, correlation analysis of AGT and KLK1 with differential renal function (DRF) from clinical samples indicated good correlation coefficients (R2 0.923, 0.8742, 0.6412, and 0.8347). This demonstrates the state of hydronephrosis could be significantly correlated with the biomarkers. These findings could provide a reliable reference for determining surgical biomarkers clinically, and ROC could be further used in the analysis of other kidney diseases.
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Affiliation(s)
- Mingming Xiao
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Lulu Zheng
- Engineering Research Center of Optical Instrument and System, Ministry of Education, Shanghai Key Lab of Modern Optical System, University of Shanghai for Science and Technology, 526 Jugong Road, Shanghai 200093, China
| | - Xinlian Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Xiaoxiao Duan
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Tian Hang
- Department of Pediatric Surgery, Jiaxing Women and Children Hospital Affiliated to Jiaxing University, 2468 East Zhonghuan Road, Jiaxing, Zhejiang 314050, China
| | - Shijiao Lu
- Department of Pediatric Surgery, Jiaxing Women and Children Hospital Affiliated to Jiaxing University, 2468 East Zhonghuan Road, Jiaxing, Zhejiang 314050, China
| | - Sixiu Liu
- Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science & Engineering, Fudan University, 2005 Songhu Road, Shanghai 200438, China
| | - Houwei Lin
- Department of Pediatric Surgery, Jiaxing Women and Children Hospital Affiliated to Jiaxing University, 2468 East Zhonghuan Road, Jiaxing, Zhejiang 314050, China
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Pal A, Asad Y, Ruddle R, Henley AT, Swales K, Decordova S, Eccles SA, Collins I, Garrett MD, De Bono J, Banerji U, Raynaud FI. Metabolomic changes of the multi (-AGC-) kinase inhibitor AT13148 in cells, mice and patients are associated with NOS regulation. Metabolomics 2020; 16:50. [PMID: 32285223 PMCID: PMC7154022 DOI: 10.1007/s11306-020-01676-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/03/2020] [Indexed: 11/26/2022]
Abstract
INTRODUCTION To generate biomarkers of target engagement or predictive response for multi-target drugs is challenging. One such compound is the multi-AGC kinase inhibitor AT13148. Metabolic signatures of selective signal transduction inhibitors identified in preclinical models have previously been confirmed in early clinical studies. This study explores whether metabolic signatures could be used as biomarkers for the multi-AGC kinase inhibitor AT13148. OBJECTIVES To identify metabolomic changes of biomarkers of multi-AGC kinase inhibitor AT13148 in cells, xenograft / mouse models and in patients in a Phase I clinical study. METHODS HILIC LC-MS/MS methods and Biocrates AbsoluteIDQ™ p180 kit were used for targeted metabolomics; followed by multivariate data analysis in SIMCA and statistical analysis in Graphpad. Metaboanalyst and String were used for network analysis. RESULTS BT474 and PC3 cells treated with AT13148 affected metabolites which are in a gene protein metabolite network associated with Nitric oxide synthases (NOS). In mice bearing the human tumour xenografts BT474 and PC3, AT13148 treatment did not produce a common robust tumour specific metabolite change. However, AT13148 treatment of non-tumour bearing mice revealed 45 metabolites that were different from non-treated mice. These changes were also observed in patients at doses where biomarker modulation was observed. Further network analysis of these metabolites indicated enrichment for genes associated with the NOS pathway. The impact of AT13148 on the metabolite changes and the involvement of NOS-AT13148- Asymmetric dimethylarginine (ADMA) interaction were consistent with hypotension observed in patients in higher dose cohorts (160-300 mg). CONCLUSION AT13148 affects metabolites associated with NOS in cells, mice and patients which is consistent with the clinical dose-limiting hypotension.
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Affiliation(s)
- Akos Pal
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Yasmin Asad
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Ruth Ruddle
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Alan T Henley
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Karen Swales
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Shaun Decordova
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Suzanne A Eccles
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | - Ian Collins
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
| | | | - Johann De Bono
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
- Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, UK
| | - Udai Banerji
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK
- Drug Development Unit, The Royal Marsden NHS Foundation Trust, Sutton, UK
| | - Florence I Raynaud
- Division of Cancer Therapeutics, The Institute of Cancer Research, London, SW7 3RP, UK.
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Vanaveski T, Narvik J, Innos J, Philips MA, Ottas A, Plaas M, Haring L, Zilmer M, Vasar E. Repeated Administration of D-Amphetamine Induces Distinct Alterations in Behavior and Metabolite Levels in 129Sv and Bl6 Mouse Strains. Front Neurosci 2018; 12:399. [PMID: 29946233 PMCID: PMC6005828 DOI: 10.3389/fnins.2018.00399] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 05/24/2018] [Indexed: 01/30/2023] Open
Abstract
The main goal of the study was to characterize the behavioral and metabolomic profiles of repeated administration (for 11 days) of d-amphetamine (AMPH, 3 mg/kg i. p.), indirect agonist of dopamine (DA), in widely used 129S6/SvEvTac (129Sv) and C57BL/6NTac (Bl6) mouse strains. Acute administration of AMPH (acute AMPH) induced significantly stronger motor stimulation in Bl6. However, repeated administration of AMPH (repeated AMPH) caused stronger motor sensitization in 129Sv compared acute AMPH. Body weight of 129Sv was reduced after repeated saline and AMPH, whereas no change occurred in Bl6. In the metabolomic study, acute AMPH induced an elevation of isoleucine and leucine, branched chain amino acids (BCAA), whereas the level of hexoses was reduced in Bl6. Both BCAAs and hexoses remained on level of acute AMPH after repeated AMPH in Bl6. Three biogenic amines [asymmetric dimethylarginine (ADMA), alpha-aminoadipic acid (alpha-AAA), kynurenine] were significantly reduced after repeated AMPH. Acute AMPH caused in 129Sv a significant reduction of valine, lysophosphatidylcholines (lysoPC a C16:0, lysoPC a C18:2, lysoPC a C20:4), phosphatidylcholine (PC) diacyls (PC aa C34:2, PC aa C36:2, PC aa C36:3, PC aa C36:4) and alkyl-acyls (PC ae C38:4, PC ae C40:4). However, repeated AMPH increased the levels of valine and isoleucine, long-chain acylcarnitines (C14, C14:1-OH, C16, C18:1), PC diacyls (PC aa C38:4, PC aa C38:6, PC aa C42:6), PC acyl-alkyls (PC ae C38:4, PC ae C40:4, PC ae C40:5, PC ae C40:6, PC ae C42:1, PC ae C42:3) and sphingolipids [SM(OH)C22:1, SM C24:0] compared to acute AMPH in 129Sv. Hexoses and kynurenine were reduced after repeated AMPH compared to saline in 129Sv. The established changes probably reflect a shift in energy metabolism toward lipid molecules in 129Sv because of reduced level of hexoses. Pooled data from both strains showed that the elevation of isoleucine and leucine was a prominent biomarker of AMPH-induced behavioral sensitization. Simultaneously a significant decline of hexoses, citrulline, ADMA, and kynurenine occurred. The reduced levels of kynurenine, ADMA, and citrulline likely reflect altered function of N-methyl-D-aspartate (NMDA) and NO systems caused by repeated AMPH. Altogether, 129Sv strain displays stronger sensitization toward AMPH and larger variance in metabolite levels than Bl6.
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Affiliation(s)
- Taavi Vanaveski
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Jane Narvik
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Jürgen Innos
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Mari-Anne Philips
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Aigar Ottas
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
- Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Mario Plaas
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
- Psychiatry Clinic and Center of Excellence for Genomics and Translational Medicine, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Liina Haring
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
- Psychiatry Clinic, Tartu University Hospital, Tartu, Estonia
| | - Mihkel Zilmer
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
- Department of Biochemistry, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Eero Vasar
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
- Center of Excellence for Genomics and Translational Medicine, University of Tartu, Tartu, Estonia
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Lumicisi BA, Cartwright JE, Leslie K, Wallace AE, Whitley GS. Inhibition of DDAH1, but not DDAH2, results in apoptosis of a human trophoblast cell line in response to TRAIL. Hum Reprod 2015; 30:1813-9. [PMID: 26082478 PMCID: PMC4507332 DOI: 10.1093/humrep/dev138] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 05/21/2015] [Indexed: 01/14/2023] Open
Abstract
STUDY QUESTION Does inhibition of dimethylarginine dimethylaminohydrolase (DDAH) increase the sensitivity of trophoblasts to TRAIL-induced apoptosis? SUMMARY ANSWER Inhibition of DDAH1, but not DDAH2, increases the sensitivity of trophoblasts to TRAIL-induced apoptosis. WHAT IS KNOWN ALREADY Successful human pregnancy is dependent on adequate trophoblast invasion and remodelling of the maternal spiral arteries. Increased trophoblast apoptosis is seen in pregnancies complicated by pre-eclampsia. The mechanism underlying this increase is unknown. We have previously shown that nitric oxide (NO) is involved in regulating trophoblast motility and invasion, and have also demonstrated an important role for NO in regulating trophoblast sensitivity to apoptotic stimuli. DDAH is an enzyme that metabolizes asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthesis, previously shown to be elevated in the plasma of pre-eclamptic mothers. STUDY DESIGN, SIZE, DURATION This study used the human extravillous trophoblast-derived cell line SGHPL-4 cells. All experiments were performed at least three times. PARTICIPANTS/MATERIALS, SETTING, METHODS The effect of DDAH on trophoblast apoptosis was examined using siRNA and time-lapse microscopy. Changes in the expression of DDAH were followed by PCR and western blot analysis. Receptor expression was followed by flow cytometry. MAIN RESULTS AND THE ROLE OF CHANCE Inhibiting the expression of DDAH1, but not DDAH2, resulted in a significant increase in the sensitivity of the EVT cell line SGHPL-4 to tumour necrosis factor related apoptosis inducing ligand (TRAIL) induced apoptosis (P < 0.01). This response could be mimicked by the addition of Asymmetric Dimethylarginine (ADMA), an endogenous inhibitor of NO synthesis and the substrate for both isoforms of DDAH. We further showed that this increased sensitivity to apoptosis is accompanied by a significant increase in the expression of TRAIL receptor 2 (TR2; P < 0.05) but not TRAIL receptor 1 (TR1). LIMITATIONS, REASONS FOR CAUTION This study was performed only in vitro using a well characterized trophoblast cell line, SGHPL-4, derived from first trimester extravillous trophoblasts. WIDER IMPLICATIONS OF THE FINDINGS This study provides new insight into the role of the DDAH/ADMA pathway in the regulation of trophoblast function. Both dysregulation of DDAH and the accumulation of ADMA have been associated with the development of pre-eclampsia. This is the first study to implicate the DDAH/ADMA pathway as a mechanism that might underlie the poor trophoblast invasion seen in this common pregnancy disorder. STUDY FUNDING/COMPETING INTEREST(S) B.A.L. was supported by a grant from Action Medical Research UK (SP4577). A.E.W. was supported by a grant from the Wellcome Trust (091550). There are no competing interests and the authors have no conflict interest to declare.
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Affiliation(s)
- B A Lumicisi
- Reproductive and Cardiovascular Research Group, Institute of Cardiovascular and Cell Sciences, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
| | - J E Cartwright
- Reproductive and Cardiovascular Research Group, Institute of Cardiovascular and Cell Sciences, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
| | - K Leslie
- Reproductive and Cardiovascular Research Group, Institute of Cardiovascular and Cell Sciences, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
| | - A E Wallace
- Reproductive and Cardiovascular Research Group, Institute of Cardiovascular and Cell Sciences, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
| | - G S Whitley
- Reproductive and Cardiovascular Research Group, Institute of Cardiovascular and Cell Sciences, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
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Bakr A, Pak O, Taye A, Hamada F, Hemeida R, Janssen W, Gierhardt M, Ghofrani HA, Seeger W, Grimminger F, Schermuly RT, Witzenrath M, Brandes RP, Huang N, Cooke JP, Weissmann N, Sommer N. Effects of dimethylarginine dimethylaminohydrolase-1 overexpression on the response of the pulmonary vasculature to hypoxia. Am J Respir Cell Mol Biol 2013; 49:491-500. [PMID: 23642043 DOI: 10.1165/rcmb.2012-0330oc] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Acute and sustained hypoxic pulmonary vasoconstriction (HPV), as well as chronic pulmonary hypertension (PH), is modulated by nitric oxide (NO). NO synthesis can be decreased by asymmetric dimethylarginine (ADMA), which is degraded by dimethylarginine dimethylaminohydrolase-1 (DDAH1). We investigated the effects of DDAH1 overexpression (DDAH1(tg)) on HPV and chronic hypoxia-induced PH. HPV was measured during acute (10 min) and sustained (3 h) hypoxia in isolated mouse lungs. Chronic PH was induced by the exposure of mice to 4 weeks of hypoxia. ADMA and cyclic 3',5'-guanosine monophosphate (cGMP) were determined by ELISA, and NO generation was determined by chemiluminescence. DDAH1 overexpression exerted no effects on acute HPV. However, DDAH1(tg) mice showed decreased sustained HPV compared with wild-type (WT) mice. Concomitantly, ADMA was decreased, and concentrations of NO and cGMP were significantly increased in DDAH1(tg). The administration of either Nω-nitro-l-arginine or 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one potentiated sustained HPV and partly abolished the differences in sustained HPV between WT and DDAH1(tg) mice. The overexpression of DDAH1 exerted no effect on the development of chronic hypoxia-induced PH. DDAH1 overexpression selectively decreased the sustained phase of HPV, partly via activation of the NO-cGMP pathway. Thus, increased ADMA concentrations modulate sustained HPV, but not acute HPV or chronic hypoxia-induced PH.
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Affiliation(s)
- Adel Bakr
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt
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Rodionov RN, Dayoub H, Lynch CM, Wilson KM, Stevens JW, Murry DJ, Kimoto M, Arning E, Bottiglieri T, Cooke JP, Baumbach GL, Faraci FM, Lentz SR. Overexpression of dimethylarginine dimethylaminohydrolase protects against cerebral vascular effects of hyperhomocysteinemia. Circ Res 2009; 106:551-8. [PMID: 20019334 DOI: 10.1161/circresaha.109.200360] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
RATIONALE Hyperhomocysteinemia is a cardiovascular risk factor that is associated with elevation of the nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA). OBJECTIVE Using mice transgenic for overexpression of the ADMA-hydrolyzing enzyme dimethylarginine dimethylaminohydrolase-1 (DDAH1), we tested the hypothesis that overexpression of DDAH1 protects from adverse structural and functional changes in cerebral arterioles in hyperhomocysteinemia. METHODS AND RESULTS Hyperhomocysteinemia was induced in DDAH1 transgenic (DDAH1 Tg) mice and wild-type littermates using a high methionine/low folate (HM/LF) diet. Plasma total homocysteine was elevated approximately 3-fold in both wild-type and DDAH1 Tg mice fed the HM/LF diet compared with the control diet (P<0.001). Plasma ADMA was approximately 40% lower in DDAH1 Tg mice compared with wild-type mice (P<0.001) irrespective of diet. Compared with the control diet, the HM/LF diet diminished endothelium-dependent dilation to 10 micromol/L acetylcholine in cerebral arterioles of both wild-type (12 + or - 2 versus 29 + or - 3%; P<0.001) and DDAH1 Tg (14 + or - 3 versus 28 + or - 2%; P<0.001) mice. Responses to 10 micromol/L papaverine, a direct smooth muscle dilator, were impaired with the HM/LF diet in wild-type mice (30 + or - 3 versus 45 + or - 5%; P<0.05) but not DDAH1 Tg mice (45 + or - 7 versus 48 + or - 6%). DDAH1 Tg mice also were protected from hypertrophy of cerebral arterioles (P<0.05) but not from accelerated carotid artery thrombosis induced by the HM/LF diet. CONCLUSIONS Overexpression of DDAH1 protects from hyperhomocysteinemia-induced alterations in cerebral arteriolar structure and vascular muscle function.
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Affiliation(s)
- Roman N Rodionov
- Department of Internal Medicine, C32 GH, The University of Iowa, Iowa City, IA 52242, USA
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Palm F, Onozato ML, Luo Z, Wilcox CS. Dimethylarginine dimethylaminohydrolase (DDAH): expression, regulation, and function in the cardiovascular and renal systems. Am J Physiol Heart Circ Physiol 2007; 293:H3227-45. [PMID: 17933965 DOI: 10.1152/ajpheart.00998.2007] [Citation(s) in RCA: 244] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Asymmetric (N(G),N(G))-dimethylarginine (ADMA) inhibits nitric oxide (NO) synthases (NOS). ADMA is a risk factor for endothelial dysfunction, cardiovascular mortality, and progression of chronic kidney disease. Two isoforms of dimethylarginine dimethylaminohydrolase (DDAH) metabolize ADMA. DDAH-1 is the predominant isoform in the proximal tubules of the kidney and in the liver. These organs extract ADMA from the circulation. DDAH-2 is the predominant isoform in the vasculature, where it is found in endothelial cells adjacent to the cell membrane and in intracellular vesicles and in vascular smooth muscle cells among the myofibrils and the nuclear envelope. In vivo gene silencing of DDAH-1 in the rat and DDAH +/- mice both have increased circulating ADMA, whereas gene silencing of DDAH-2 reduces vascular NO generation and endothelium-derived relaxation factor responses. DDAH-2 also is expressed in the kidney in the macula densa and distal nephron. Angiotensin type 1 receptor activation in kidneys reduces the expression of DDAH-1 but increases the expression of DDAH-2. This rapidly evolving evidence of isoform-specific distribution and regulation of DDAH expression in the kidney and blood vessels provides potential mechanisms for nephron site-specific regulation of NO production. In this review, the recent advances in the regulation and function of DDAH enzymes, their roles in the regulation of NO generation, and their possible contribution to endothelial dysfunction in patients with cardiovascular and kidney diseases are discussed.
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Affiliation(s)
- Fredrik Palm
- Division of Nephrology and Hypertension, Georgetown University, 3800 Reservoir Road N.W., Washington, DC 20007, USA
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