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Norabuena E, Leffler-Griffin L, Mao A, Dixon T, Stein S, Sacks IS, Ocola L, Ellis M. Space geodetic observations of nazca-south america convergence across the central andes. Science 1998; 279:358-62. [PMID: 9430582 DOI: 10.1126/science.279.5349.358] [Citation(s) in RCA: 203] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Space geodetic data recorded rates and directions of motion across the convergent boundary zone between the oceanic Nazca and continental South American plates in Peru and Bolivia. Roughly half of the overall convergence, about 30 to 40 millimeters per year, accumulated on the locked plate interface and can be released in future earthquakes. About 10 to 15 millimeters per year of crustal shortening occurred inland at the sub-Andean foreland fold and thrust belt, indicating that the Andes are continuing to build. Little (5 to 10 millimeters per year) along-trench motion of coastal forearc slivers was observed, despite the oblique convergence.
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Newman A, Stein S, Weber J, Engeln J, Mao A, Dixon T. Slow deformation and lower seismic hazard at the new madrid seismic zone. Science 1999; 284:619-21. [PMID: 10213680 DOI: 10.1126/science.284.5414.619] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Global Positioning System (GPS) measurements across the New Madrid seismic zone (NMSZ) in the central United States show little, if any, motion. These data are consistent with platewide continuous GPS data away from the NMSZ, which show no motion within uncertainties. Both these data and the frequency-magnitude relation for seismicity imply that had the largest shocks in the series of earthquakes that occurred in 1811 and 1812 been magnitude 8, their recurrence interval should well exceed 2500 years, longer than has been assumed. Alternatively, the largest 1811 and 1812 earthquakes and those in the paleoseismic record may have been much smaller than typically assumed. Hence, the hazard posed by great earthquakes in the NMSZ appears to be overestimated.
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Sobolev NV, Fursenko BA, Goryainov SV, Shu J, Hemley RJ, Mao A, Boyd FR. Fossilized high pressure from the Earth's deep interior: the coesite-in-diamond barometer. Proc Natl Acad Sci U S A 2000; 97:11875-9. [PMID: 11035808 PMCID: PMC17262 DOI: 10.1073/pnas.220408697] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mineral inclusions in diamonds provide an important source of information about the composition of the continental lithosphere at depths exceeding 120-150 km, i.e., within the diamond stability field. Fossilized high pressures in coesite inclusions from a Venezuela diamond have been identified and measured by using laser Raman and synchrotron x-ray microanalytical techniques. Micro-Raman measurements on an intact inclusion of remnant vibrational band shifts give a high confining pressure of 3.62 (+/-0.18) GPa. Synchrotron single-crystal diffraction measurements of the volume compression are in accord with the Raman results and also revealed direct structural information on the state of the inclusion. In contrast to olivine and garnet inclusions, the thermoelasticity of coesite favors accurate identification of pressure preservation. Owing to the unique combination of physical properties of coesite and diamond, this "coesite-in-diamond" geobarometer is virtually independent of temperature, allowing an estimation of the initial pressure of Venezuela diamond formation of 5.5 (+/-0.5) GPa.
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Liu DQ, Hop CE, Beconi MG, Mao A, Chiu SH. Use of on-line hydrogen/deuterium exchange to facilitate metabolite identification. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:1832-1839. [PMID: 11565101 DOI: 10.1002/rcm.442] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Biotransformation studies performed on an investigational compound (I, represented by R1-CH(NH(2))-CO-N(R2)-CH(2)-S-R3) led to the identification of five metabolites (M1-M5). Based on LC/MS (liquid chromatography/mass spectrometry) analysis which included the use of H(2)O and D(2)O in the mobile phases, they were identified as the sulfoxide (M1), sulfone (M2), carbamoyl glucuronide (M3), N-glucuronide (M4), and N-glucoside (M5) metabolites, respectively. The structure of M3, a less commonly seen carbamoyl glucuronide metabolite, was established using on-line H/D (hydrogen/deuterium) exchange experiments conducted by LC/MS. H/D exchange experiments were also used to distinguish the S-oxidation structures of M1 and M2 from hydroxylation. Herein, the application of deuterium oxide as the LC/MS mobile phase for structural elucidation of drug metabolites in biological matrices is demonstrated.
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Day SH, Mao A, White R, Schulz-Utermoehl T, Miller R, Beconi MG. A semi-automated method for measuring the potential for protein covalent binding in drug discovery. J Pharmacol Toxicol Methods 2005; 52:278-85. [PMID: 16125627 DOI: 10.1016/j.vascn.2004.11.006] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 11/15/2004] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Covalent protein binding of metabolically reactive intermediates of drugs has been implicated in drug toxicity including the occurrence of idiosyncratic drug toxicity. Investigators therefore would prefer to avoid developing compounds that produce significant amounts of reactive metabolites. By incubating the radiolabeled drug of interest with liver microsomes it is possible to evaluate the propensity of a drug candidate to covalently bind to proteins. METHODS Here we present a semi-automated method in which a Brandel cell harvester is used to collect and wash proteins that have been incubated with radiolabeled drug. This method utilizes glass fiber filter paper to capture precipitated protein, rather than the more traditional exhaustive extraction/centrifugation approach. Using model compounds (including [14C]diclofenac, [3H]imipramine, [14C]naphthalene, and [14C]L-746530) we compare the covalent binding results obtained using this method to results generated using the traditional method and we performed cross-laboratory testing of assay reproducibility. RESULTS It was found that results from new method correlated highly with the traditional method (R2=0.89). The cross-laboratory testing of the method showed an average interlaboratory coefficient of variation of only 18.4%. DISCUSSION This method provides comparable results to the more traditional centrifugation-based method with considerable time and labor savings.
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Zhang WX, Chen B, Jin Z, Yu Z, Wang X, Chen H, Mao A, Cai W. Influence of uridine diphosphate (UDP)-glucuronosyltransferases and ABCC2 genetic polymorphisms on the pharmacokinetics of mycophenolic acid and its metabolites in Chinese renal transplant recipients. Xenobiotica 2008; 38:1422-36. [DOI: 10.1080/00498250802488585] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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He DX, Gu F, Gao F, Hao JJ, Gong D, Gu XT, Mao AQ, Jin J, Fu L, Ma X. Genome-wide profiles of methylation, microRNAs, and gene expression in chemoresistant breast cancer. Sci Rep 2016; 6:24706. [PMID: 27094684 PMCID: PMC4837395 DOI: 10.1038/srep24706] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 03/30/2016] [Indexed: 12/17/2022] Open
Abstract
Cancer chemoresistance is regulated by complex genetic and epigenetic networks. In this study, the features of gene expression, methylation, and microRNA (miRNA) expression were investigated with high-throughput sequencing in human breast cancer MCF-7 cells resistant to adriamycin (MCF-7/ADM) and paclitaxel (MCF-7/PTX). We found that: ① both of the chemoresistant cell lines had similar, massive changes in gene expression, methylation, and miRNA expression versus chemosensitive controls. ② Pairwise integration of the data highlighted sets of genes that were regulated by either methylation or miRNAs, and sets of miRNAs whose expression was controlled by DNA methylation in chemoresistant cells. ③ By combining the three sets of high-throughput data, we obtained a list of genes whose expression was regulated by both methylation and miRNAs in chemoresistant cells; ④ Expression of these genes was then validated in clinical breast cancer samples to generate a 17-gene signature that showed good predictive and prognostic power in triple-negative breast cancer patients receiving anthracycline-taxane-based neoadjuvant chemotherapy. In conclusion, our results have generated a new workflow for the integrated analysis of the effects of miRNAs and methylation on gene expression during the development of chemoresistance.
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Research Support, Non-U.S. Gov't |
9 |
35 |
8
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Zhang P, Sun C, Li H, Tang C, Kan H, Yang Z, Mao A, Ma X. TRPV4 (Transient Receptor Potential Vanilloid 4) Mediates Endothelium-Dependent Contractions in the Aortas of Hypertensive Mice. Hypertension 2017; 71:134-142. [PMID: 29109190 DOI: 10.1161/hypertensionaha.117.09767] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 06/06/2017] [Accepted: 09/13/2017] [Indexed: 11/16/2022]
Abstract
The role of TRPV4 (transient receptor potential vanilloid 4) in regulating vascular contraction in hypertensive mice is poorly established. We tested the hypothesis that TRPV4 regulates endothelium-dependent contractions in aortas from hypertensive mice through the activation of cytosolic cPLA2 (phospholipase A2) and COX2 (cyclooxygenase 2) and identified the possible endothelium-derived contracting factor generated by COX2. Using myography, we demonstrated that GSK1016790A (a TRPV4 agonist) and acetylcholine (ACh) trigger endothelium-dependent contractions in aortas from hypertensive mice, and the contractions were abolished with TRPV4 deletion. PLA2 assay and Western blotting showed that cPLA2 activity was higher in salt-induced hypertension and HC067047 or a Ca2+ chelator inhibited cPLA2 activity. Contractions induced by TRPV4 and ACh were inhibited by the cPLA2 inhibitor or removal of extracellular Ca2+ COX2 expression was enhanced in the endothelium from hypertensive mice and contractions induced by TRPV4 or ACh were inhibited by the COX2 inhibitor. Enzyme immunoassay showed that the release of prostaglandin F2α (PGF2α) was increased in hypertensive mice. GSK1016790A or ACh triggered the release of PGF2α and this was inhibited by HC067047, the cPLA2 inhibitor, and COX2 inhibitor. GSK1016790A, ACh, and PGF2α induced contractions were significantly reduced by S18886 in salt-induced hypertensive mice. The present study demonstrates that PGF2α generated by COX2 in the endothelium is the most likely endothelium-derived contracting factor underlying endothelium-dependent, TRPV4-mediated contraction in hypertensive mice. This contraction involved increased intracellular Ca2+ concentrations and cPLA2 activity. These results suggested an important role of TRPV4 in endothelium-dependent contraction in mice during hypertension.
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Research Support, Non-U.S. Gov't |
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He D, Mao A, Zheng CB, Kan H, Zhang K, Zhang Z, Feng L, Ma X. Aortic heterogeneity across segments and under high fat/salt/glucose conditions at the single-cell level. Natl Sci Rev 2020; 7:881-896. [PMID: 34692110 PMCID: PMC8289085 DOI: 10.1093/nsr/nwaa038] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 01/23/2020] [Accepted: 02/08/2020] [Indexed: 12/24/2022] Open
Abstract
The aorta, with ascending, arch, thoracic and abdominal segments, responds to the heartbeat, senses metabolites and distributes blood to all parts of the body. However, the heterogeneity across aortic segments and how metabolic pathologies change it are not known. Here, a total of 216 612 individual cells from the ascending aorta, aortic arch, and thoracic and abdominal segments of mouse aortas under normal conditions or with high blood glucose levels, high dietary salt, or high fat intake were profiled using single-cell RNA sequencing. We generated a compendium of 10 distinct cell types, mainly endothelial (EC), smooth muscle (SMC), stromal and immune cells. The distributions of the different cells and their intercommunication were influenced by the hemodynamic microenvironment across anatomical segments, and the spatial heterogeneity of ECs and SMCs may contribute to differential vascular dilation and constriction that were measured by wire myography. Importantly, the composition of aortic cells, their gene expression profiles and their regulatory intercellular networks broadly changed in response to high fat/salt/glucose conditions. Notably, the abdominal aorta showed the most dramatic changes in cellular composition, particularly involving ECs, fibroblasts and myeloid cells with cardiovascular risk factor-related regulons and gene expression networks. Our study elucidates the nature and range of aortic cell diversity, with implications for the treatment of metabolic pathologies.
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He D, Pan Q, Chen Z, Sun C, Zhang P, Mao A, Zhu Y, Li H, Lu C, Xie M, Zhou Y, Shen D, Tang C, Yang Z, Jin J, Yao X, Nilius B, Ma X. Treatment of hypertension by increasing impaired endothelial TRPV4-KCa2.3 interaction. EMBO Mol Med 2018; 9:1491-1503. [PMID: 28899928 PMCID: PMC5666316 DOI: 10.15252/emmm.201707725] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The currently available antihypertensive agents have undesirable adverse effects due to systemically altering target activity including receptors, channels, and enzymes. These effects, such as loss of potassium ions induced by diuretics, bronchospasm by beta‐blockers, constipation by Ca2+ channel blockers, and dry cough by ACEI, lead to non‐compliance with therapies (Moser, 1990). Here, based on new hypertension mechanisms, we explored a new antihypertensive approach. We report that transient receptor potential vanilloid 4 (TRPV4) interacts with Ca2+‐activated potassium channel 3 (KCa2.3) in endothelial cells (ECs) from small resistance arteries of normotensive humans, while ECs from hypertensive patients show a reduced interaction between TRPV4 and KCa2.3. Murine hypertension models, induced by high‐salt diet, N(G)‐nitro‐l‐arginine intake, or angiotensin II delivery, showed decreased TRPV4‐KCa2.3 interaction in ECs. Perturbation of the TRPV4‐KCa2.3 interaction in mouse ECs by overexpressing full‐length KCa2.3 or defective KCa2.3 had hypotensive or hypertensive effects, respectively. Next, we developed a small‐molecule drug, JNc‐440, which showed affinity for both TRPV4 and KCa2.3. JNc‐440 significantly strengthened the TRPV4‐KCa2.3 interaction in ECs, enhanced vasodilation, and exerted antihypertensive effects in mice. Importantly, JNc‐440 specifically targeted the impaired TRPV4‐KCa2.3 interaction in ECs but did not systemically activate TRPV4 and KCa2.3. Together, our data highlight the importance of impaired endothelial TRPV4‐KCa2.3 coupling in the progression of hypertension and suggest a novel approach for antihypertensive drug development.
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Research Support, Non-U.S. Gov't |
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28 |
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Zhu Y, Pan Q, Meng H, Jiang Y, Mao A, Wang T, Hua D, Yao X, Jin J, Ma X. Enhancement of vascular endothelial growth factor release in long-term drug-treated breast cancer via transient receptor potential channel 5-Ca2+-hypoxia-inducible factor 1α pathway. Pharmacol Res 2015; 93:36-42. [DOI: 10.1016/j.phrs.2014.12.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 12/29/2014] [Accepted: 12/30/2014] [Indexed: 12/24/2022]
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Shah S, Ceska R, Gil-Extremera B, Paolini JF, Giezek H, Vandormael K, Mao A, McCrary Sisk C, Maccubbin D. Efficacy and safety of extended-release niacin/laropiprant plus statin vs. doubling the dose of statin in patients with primary hypercholesterolaemia or mixed dyslipidaemia. Int J Clin Pract 2010; 64:727-38. [PMID: 20518948 DOI: 10.1111/j.1742-1241.2010.02370.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Co-administration of niacin with statin offers the potential for additional lipid management and cardiovascular risk reduction. However, niacin is underutilised because of the side effects of flushing, mediated primarily by prostaglandin D(2) (PGD(2)). A combination tablet containing extended-release niacin and laropiprant (ERN/LRPT), a PGD(2) receptor (DP1) antagonist, offers improved tolerability. This study assessed the efficacy and safety of ERN/LRPT added to statin vs. doubling the dose of statin in patients with primary hypercholesterolaemia or mixed dyslipidaemia who were not at their National Cholesterol Education Program Adult Treatment Panel III low-density lipoprotein cholesterol (LDL-C) goal based on their coronary heart disease risk category (high, moderate or low). METHODS After a 2- to 6-week run-in statin (simvastatin 10 or 20 mg or atorvastatin 10 mg) period, 1216 patients were randomised equally to one of two treatment groups in a double-blind fashion: group 1 received ERN/LRPT (1 g) plus the run-in statin dose and advanced to ERN/LRPT (2 g) after 4 weeks for an additional 8 weeks, with no adjustments to the run-in statin dose; group 2 received simvastatin or atorvastatin at twice their run-in statin dose and remained on this stable dose for 12 weeks. RESULTS ERN/LRPT added to statin (pooled across statin and statin dose) significantly improved key lipid parameters vs. the doubled statin dose (pooled): the between-treatment group difference in least squares mean per cent change [95% confidence interval (CI)] from baseline to week 12 in LDL-C (primary end-point) was -4.5% (-7.7, -1.3) and in high-density lipoprotein cholesterol (HDL-C) was 15.6% (13.4, 17.9) and in median per cent change for triglyceride (TG) was -15.4% (-19.2, -11.7). Treatment-related adverse experiences (AEs) related to flushing, pruritis, rash, gastrointestinal upset and elevations in liver transaminases and fasting serum glucose occurred more frequently with ERN/LRPT added to statin vs. statin dose doubled. CONCLUSIONS The addition of ERN/LRPT to ongoing statin treatment produced significantly improved lipid-modifying benefits on LDL-C, HDL-C and TG and all other lipid parameters compared with doubling the statin dose in patients with primary hypercholesterolaemia or mixed dyslipidaemia. The types of AEs that occurred at a greater frequency in the ERN/LRPT group were those typically associated with niacin.
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Comparative Study |
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Kan H, Zhang K, Mao A, Geng L, Gao M, Feng L, You Q, Ma X. Single-cell transcriptome analysis reveals cellular heterogeneity in the ascending aortas of normal and high-fat diet-fed mice. Exp Mol Med 2021; 53:1379-1389. [PMID: 34548614 PMCID: PMC8492660 DOI: 10.1038/s12276-021-00671-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/13/2021] [Accepted: 07/21/2021] [Indexed: 01/26/2023] Open
Abstract
The aorta contains numerous cell types that contribute to vascular inflammation and thus the progression of aortic diseases. However, the heterogeneity and cellular composition of the ascending aorta in the setting of a high-fat diet (HFD) have not been fully assessed. We performed single-cell RNA sequencing on ascending aortas from mice fed a normal diet and mice fed a HFD. Unsupervised cluster analysis of the transcriptional profiles from 24,001 aortic cells identified 27 clusters representing 10 cell types: endothelial cells (ECs), fibroblasts, vascular smooth muscle cells (SMCs), immune cells (B cells, T cells, macrophages, and dendritic cells), mesothelial cells, pericytes, and neural cells. After HFD intake, subpopulations of endothelial cells with lipid transport and angiogenesis capacity and extensive expression of contractile genes were defined. In the HFD group, three major SMC subpopulations showed increased expression of extracellular matrix-degradation genes, and a synthetic SMC subcluster was proportionally increased. This increase was accompanied by upregulation of proinflammatory genes. Under HFD conditions, aortic-resident macrophage numbers were increased, and blood-derived macrophages showed the strongest expression of proinflammatory cytokines. Our study elucidates the nature and range of the cellular composition of the ascending aorta and increases understanding of the development and progression of aortic inflammatory disease.
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Zhu Y, Gao M, Zhou T, Xie M, Mao A, Feng L, Yao X, Wong WT, Ma X. The TRPC5 channel regulates angiogenesis and promotes recovery from ischemic injury in mice. J Biol Chem 2018; 294:28-37. [PMID: 30413532 DOI: 10.1074/jbc.ra118.005392] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 11/06/2018] [Indexed: 11/06/2022] Open
Abstract
Ischemia-related diseases are a leading cause of death worldwide, and promoting therapeutic angiogenesis is key for effective recovery from hypoxia-ischemia. Given the limited success of angiogenic factors, such as vascular endothelial growth factor, in clinical trials, it is important to find more promising angiogenic targets. Here, using both cell- and tissue-based assays and a mouse model of injury-induced ischemia, we investigated the involvement of the transient receptor potential canonical 5 (TRPC5) ion channel in angiogenesis and the effects of a TRPC5 activator, the Food and Drug Administration-approved drug riluzole, on recovery from ischemic injury. We demonstrate that TRPC5 is involved in endothelial cell sprouting, angiogenesis, and blood perfusion in an oxygen-induced retinopathy model and a hind limb ischemia model. We found a potential regulatory link between nuclear factor of activated T cell isoform c3 and angiopoietin-1 that could provide the mechanistic basis for the angiogenic function of TRPC5. Importantly, treatment with riluzole, which can activate TRPC5 in endothelial cells, improved recovery from ischemia in mice. Our study reveals TRPC5 as a potential angiogenic target and suggests riluzole as a promising drug for managing ischemic diseases.
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Research Support, Non-U.S. Gov't |
7 |
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Eggert JH, Karmon E, Hemley RJ, Mao A, Goncharov AF. Pressure-enhanced ortho-para conversion in solid hydrogen up to 58 GPa. Proc Natl Acad Sci U S A 1999; 96:12269-72. [PMID: 10535910 PMCID: PMC22905 DOI: 10.1073/pnas.96.22.12269] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/18/1999] [Indexed: 11/18/2022] Open
Abstract
We measured the ortho-para conversion rate in solid hydrogen by using Raman scattering in a diamond-anvil cell, extending previous measurements by a factor of 60 in pressure. We confirm previous experiments that suggested a decrease in the conversion rate above about 0.5 GPa. We observe a distinct minimum at 3 GPa followed by a drastic increase in the conversion rate to our maximum pressure of 58 GPa. This pressure enhancement of conversion is not predicted by previous theoretical treatments and must be due to a new conversion pathway.
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He D, Mao A, Li Y, Tam S, Zheng Y, Yao X, Birnbaumer L, Ambudkar IS, Ma X. TRPC1 participates in the HSV-1 infection process by facilitating viral entry. SCIENCE ADVANCES 2020; 6:eaaz3367. [PMID: 32206724 PMCID: PMC7080438 DOI: 10.1126/sciadv.aaz3367] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 12/20/2019] [Indexed: 06/10/2023]
Abstract
Mammalian transient receptor potential (TRP) channels are major components of Ca2+ signaling pathways and control a diversity of physiological functions. Here, we report a specific role for TRPC1 in the entry of herpes simplex virus type 1 (HSV-1) into cells. HSV-1-induced Ca2+ release and entry were dependent on Orai1, STIM1, and TRPC1. Inhibition of Ca2+ entry or knockdown of these proteins attenuated viral entry and infection. HSV-1 glycoprotein D interacted with the third ectodomain of TRPC1, and this interaction facilitated viral entry. Knockout of TRPC1 attenuated HSV-1-induced ocular abnormality and morbidity in vivo in TRPC1-/- mice. There was a strong correlation between HSV-1 infection and plasma membrane localization of TRPC1 in epithelial cells within oral lesions in buccal biopsies from HSV-1-infected patients. Together, our findings demonstrate a critical role for TRPC1 in HSV-1 infection and suggest the channel as a potential target for anti-HSV therapy.
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Research Support, N.I.H., Intramural |
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Mao A, Jin X, Gu X, Wei X, Yang G. Rapid, green synthesis and surface-enhanced Raman scattering effect of single-crystal silver nanocubes. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.04.043] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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He DX, Li GH, Gu XT, Zhang L, Mao AQ, Wei J, Liu DQ, Shi GY, Ma X. A new agent developed by biotransformation of polyphyllin VII inhibits chemoresistance in breast cancer. Oncotarget 2017; 7:31814-24. [PMID: 26701723 PMCID: PMC5077978 DOI: 10.18632/oncotarget.6674] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 12/05/2015] [Indexed: 11/25/2022] Open
Abstract
Biotransformation by the endophytes of certain plants changes various compounds, and this ‘green’ chemistry becomes increasingly important for finding new products with pharmacological activity. In this study, polyphyllin VII (PPL7) was biotransformed by endophytes from the medicinal plant Paris polyphylla Smith, var. yunnanensis. This produced a new compound, ZH-2, with pharmacological activity in vitro and in vivo. ZH-2 was more potent than PPL7 in selectively killing more chemoresistant than chemosensitive breast cancer cells. ZH-2 also re-sensitized chemoresistant breast cancer cells, as evidenced by the improved anti-cancer activity of commonly-used chemotherapeutic agent in vitro, in vivo, and in clinical samples. This anti-chemoresistance effect of ZH-2 was associated with inhibiting the epithelial-mesenchymal transition (EMT) pathway. Taken together, our findings are the first one to link biotransformation with a biomedicine. The results provide insights into developing new pharmacologically-active agents via biotransformation by endophytes.
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Journal Article |
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Fang DL, Wu BC, Yan Y, Mao AQ, Zheng CH. Synthesis and characterization of mesoporous Mn–Ni oxides for supercapacitors. J Solid State Electrochem 2011. [DOI: 10.1007/s10008-011-1306-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Zhang Z, Wu X, Zhang L, Mao A, Ma X, He D. Menthol relieves acid reflux inflammation by regulating TRPV1 in esophageal epithelial cells. Biochem Biophys Res Commun 2020; 525:S0006-291X(20)30318-1. [PMID: 32081421 DOI: 10.1016/j.bbrc.2020.02.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
Abstract
Transient receptor potential cation channel subfamily V member 1 (TRPV1) plays an important role in pain and inflammatory responses. Previous studies have shown that the expression of TRPV1 increases in the sensory neurons of the esophagus during the development of gastroesophageal reflux disease and esophagitis, but the response of TRPV1 in esophageal epithelial cells (EECs), which directly confront the refluxed acid, is still unknown. Here, we found that acid reflux triggered esophageal damage, which was accompanied by increased expression of TRPV1 in EECs and TRPV1 channel activity in these cells. Furthermore, menthol inhibited the Ca2+ influx induced by acid stimulation in EECs. After menthol treatment, the expression of TRPV1 in EECs was significantly reduced, and their hyperplasia was significantly reduced; finally, the inflammation pathway elicited in EECs was diminished in mice with acid reflux. These results suggest that menthol improves the clinical symptoms caused by gastroesophageal acid reflux by interfering with TRPV1 in EECs.
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Zhou T, Wang Z, Guo M, Zhang K, Geng L, Mao A, Yang Y, Yu F. Puerarin induces mouse mesenteric vasodilation and ameliorates hypertension involving endothelial TRPV4 channels. Food Funct 2021; 11:10137-10148. [PMID: 33155599 DOI: 10.1039/d0fo02356f] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Puerarin (Pue) is an isoflavone derived from the root of Pueraria lobata, which has been widely used as food and a herb for treating cardiovascular and cerebrovascular diseases. Transient receptor potential vanilloid 4 (TRPV4), a Ca2+-permeable channel with multiple modes of activation, plays an important role in vascular endothelial function and vasodilation. However, no reports have shown the effects of Pue on TRPV4 channels and mouse small mesenteric arteries. In the present study, we performed a molecular docking assay by using Discovery Studio 3.5 software to predict the binding of Pue to TRPV4 protein. The activation of TRPV4 by Pue was determined by intracellular Ca2+ concentration ([Ca2+]i), live-cell fluorescent Ca2+ imaging and patch clamp assays. Molecular docking results indicated a high possibility of Pue-TPRV4 binding. [Ca2+]i and Ca2+ imaging assays showed that Pue activated TRPV4 channels and increased [Ca2+]i in TRPV4-overexpressing HEK293 (TRPV4-HEK293) cells and primary mouse mesenteric artery endothelial cells (MAECs). Patch clamp assay demonstrated that Pue stimulated the TRPV4-mediated cation currents. Additionally, Pue relaxed mouse mesenteric arteries involving the TRPV4-small-conductance Ca2+-activated K+ channel (SKCa)/intermediate-conductance Ca2+-activated K+ channel (IKCa) pathway, and reduced systolic blood pressure (SBP) in high-salt-induced hypertensive mice. Our study found for the first time that Pue acts as a TRPV4 agonist, induces endothelium-dependent vasodilation in mouse mesenteric arteries, and attenuates blood pressure in high-salt-induced hypertensive mice, highlighting the beneficial effect of Pue in treating endothelial dysfunction-related cardiovascular diseases.
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Zhang X, Mao A, Xiao W, Zhang P, Han X, Zhou T, Chen Y, Jin J, Ma X. Morin induces endothelium-dependent relaxation by activating TRPV4 channels in rat mesenteric arteries. Eur J Pharmacol 2019; 859:172561. [PMID: 31326379 DOI: 10.1016/j.ejphar.2019.172561] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 10/26/2022]
Abstract
Morin, a natural flavonol, has been reported to have beneficial pharmacological effects. Although its vascular protective effects have been studied, little is known about its effects on the mesenteric artery and the underlying mechanisms. Transient receptor potential vanilloid type 4 (TRPV4) channels are one of the most important Ca2+-permeable cation channels in vascular endothelial cells and play an important role in regulating rat mesenteric vascular tone. In the present study, the myogenic effects of morin were investigated using wire and pressure myography in the isolated mesenteric artery. Morin induced endothelium-dependent relaxation of isolated rat mesenteric arteries in a concentration-dependent manner. In addition, morin stimulated relaxation by activating TRPV4-mediated Ca2+ influx without affecting the nitric oxide (NO), hydrogen peroxide (H2O2), cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) pathways. In primary cultured rat mesenteric artery endothelial cells and over-expressing TRPV4 HEK 293 cells, the TRPV4 inhibitor HC067047 significantly reduced the morin-induced increase in intracellular Ca2+ concentration. Furthermore, in rats with hypertension induced by NꞶ-nitro-L-arginine methyl ester (L-NAME), oral administration of morin (50 mg/kg/day) decreased systolic blood pressure. In L-NAME-induced hypertensive rats, morin significantly improved the relaxation response of the arteries to acetylcholine. Thus, we demonstrated that morin induces endothelium-dependent relaxation in the rat mesenteric artery by acting on TRPV4 channels to mediate Ca2+ influx and attenuate blood pressure in L-NAME-induced hypertension, thereby highlighting the potential of morin in the treatment of hypertension.
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Cui Y, Lu C, Zhang Z, Mao A, Feng L, Fu L, Gu F, Ma X, He D. A Long Non-coding RNA Lnc712 Regulates Breast Cancer Cell Proliferation. Int J Biol Sci 2020; 16:162-171. [PMID: 31892853 PMCID: PMC6930380 DOI: 10.7150/ijbs.36429] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/29/2019] [Indexed: 12/22/2022] Open
Abstract
Great quantity of intergenic noncoding RNAs (lncRNAs) have been identified in the mammalian genome and involved in various biological processes, especially in the development and metastasis of cancer. In this study, we identified one lncRNA, lncRNA NONHSAT028712 (Lnc712), was highly expressed in breast cancer cell lines and tissues based on microarray screening. Knockdown of Lnc712 largely inhibited breast cancer cell proliferation. Mechanistically, Lnc712 bound specifically to heat-shock protein 90 (HSP90). Interaction between Lnc712 and HSP90 is required for HSP90 binding to cell division cycle 37 (Cdc37). The Lnc712/HSP90/Cdc37 complex regulated cyclin-dependent kinase 2 (CDK2) activation and then triggered breast cancer cell proliferation. In summary, our results identified a new lncRNA regulate breast cancer proliferation though interaction with HSP90.
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Mao A, Zhang P, Zhang K, Kan H, He D, Han X, Wang Z, Tang C, Ma X. Endothelial TRPV4-eNOS coupling as a vital therapy target for treatment of hypertension. Br J Pharmacol 2021; 179:2297-2312. [PMID: 34822720 DOI: 10.1111/bph.15755] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 10/25/2021] [Accepted: 11/10/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Reduced nitric oxide (NO) level and activity are signs of endothelial dysfunction, which is important in mediating blood pressure up-regulation. Previously, we demonstrated that transient receptor potential channel V4 (TRPV4) could form functional complex with other proteins to mediate vasodilation in the Endothelial cells (ECs). But how TRPV4 interacts with the NO pathway in larger arteries requires further exploration. EXPERIMENTAL APPROACH We used single-cell RNA-sequencing to find the CD106+ TRPV4high NOS3high ECs. The TRPV4-eNOS interaction was verified by co-immunoprecipitation and Immunofluorescence resonance energy transfer (FRET), and their binding site was found by site-directed mutagenesis. Endothelium-specific TRPV4 knockout (TRPV4EC -/- ) mice were used to study the effect of the TRPV4-eNOS interaction on blood pressure. A small molecule, JNc-463 was designed through molecular docking technology. KEY RESULTS We uncovered CD106+ TRPV4high NOS3high ECs in the mouse aorta, which they could regulate vasodilation via a TRPV4-eNOS interaction, and they were essential to regulate blood pressure. The TRPV4-eNOS interaction markedly decreased during the process of hypertension. We further attempted to identify the molecules re-join the TRPV4-eNOS interaction and develop a small-molecule drug, JNc-463, which could increase the TRPV4-eNOS interaction to enhance vasodilation, and exert antihypertensive effects in mice. CONCLUSION AND IMPLICATIONS This is the first study integrating single-cell RNA-Seq, single-cell functional study and drug screening in aorta. We identified a subpopulation of CD106+ TRPV4high NOS3high ECs, in which an impaired TRPV4-eNOS interaction was important in the progress of hypertension and we designed a small molecule, JNc-463 to improve the impaired TRPV4-eNOS interaction in hypertension.
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Wen L, Mao A, Jiao F, Zhang D, Xie J, He K. Evidence of porcine circovirus-like virus P1 in piglets with an unusual congenital tremor. Transbound Emerg Dis 2017; 65:e501-e504. [DOI: 10.1111/tbed.12772] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Indexed: 01/07/2023]
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