276
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Belanger S, Ma W, Chabot JG, Quirion R. Expression of calcitonin gene-related peptide, substance P and protein kinase C in cultured dorsal root ganglion neurons following chronic exposure to mu, delta and kappa opiates. Neuroscience 2003; 115:441-53. [PMID: 12421610 DOI: 10.1016/s0306-4522(02)00452-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The mechanisms involved in morphine tolerance are poorly understood. It was reported by our group that calcitonin gene-related peptide (CGRP)-like immunoreactivity (IR) was increased in the spinal dorsal horn during morphine tolerance [Ménard et al. (1996) J. Neurosci. 16, 2342-2351]. More recently, we observed that it was possible to mimic these results in cultured dorsal root ganglion (DRG) neurons allowing for more detailed mechanistic studies [Ma et al. (2000) Neuroscience 99, 529-539]. The aim of the present series of experiments was to further validate the DRG cell culture model by establishing which subtypes of opioid receptors are involved in the induction of CGRP in cultured rat DRG neurons, and to examine the signaling pathway possibly involved in the induction of CGRP-like IR following repeated opiate treatments. Other neuropeptides known to be expressed in DRG neurons, such as substance P (SP), neuropeptide Y (NPY) and galanin, were investigated to assess specificity. Following treatment with any of the three opioid agonists (mu, DAMGO; delta, DPDPE; kappa, U50488H), the number of CGRP- and SP-IR cultured DRG neurons increased significantly, and in a concentration-dependent manner, with the effects of kappa agonist being less pronounced. NPY and galanin were not affected.Double-immunofluorescence staining showed that the three opioid receptors were co-localized with both CGRP- and SP-like IR.Protein kinase C (PKC)-like IR was found to be significantly increased following a repetitive treatment with DAMGO. Double-immunofluorescence staining showed the co-localization of PKCalpha with CGRP- and SP-IR in cultured DRG neurons. Moreover, a combined treatment with DAMGO and a PKC inhibitor (chelerythrine chloride or Gö 6976) was able to block the effects of the opioid on increased CGRP-like IR. These data suggest that the three opioid receptors may be involved in the induction of CGRP and SP observed following chronic exposure to opiates, and that PKC probably plays a role in the signaling pathway leading to the up-regulation of these neuropeptides. These findings further validate the DRG cell culture as a suitable model to study intracellular pathways that govern changes seen following repeated opioid treatments possibly leading to opioid tolerance.
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Analgesics, Non-Narcotic/pharmacology
- Analgesics, Opioid/pharmacology
- Animals
- Calcitonin Gene-Related Peptide/analysis
- Cells, Cultured
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology
- Enkephalin, D-Penicillamine (2,5)-/pharmacology
- Galanin/analysis
- Ganglia, Spinal/cytology
- Isoenzymes/analysis
- Isoenzymes/antagonists & inhibitors
- Male
- Neurons, Afferent/chemistry
- Neurons, Afferent/drug effects
- Neurons, Afferent/enzymology
- Neuropeptide Y/analysis
- Protein Kinase C/analysis
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C-alpha
- Rats
- Rats, Sprague-Dawley
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/analysis
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/analysis
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/analysis
- Substance P/analysis
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277
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Ma W, Chou I, Karaki T, Cross L. Dielectric and Field-Induced Piezoelectric Responses in Electron-Irradiated Poly(Vinylidene Fluoride- Trifluoroethylene) Copolymer. ACTA ACUST UNITED AC 2002. [DOI: 10.1002/1521-396x(200211)194:1<349::aid-pssa349>3.0.co;2-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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278
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Lin HJ, Shaffer KM, Chang YH, Barker JL, Pancrazio JJ, Stenger DA, Ma W. Acute exposure of toluene transiently potentiates p42/44 mitogen-activated protein kinase (MAPK) activity in cultured rat cortical astrocytes. Neurosci Lett 2002; 332:103-6. [PMID: 12384221 DOI: 10.1016/s0304-3940(02)00930-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
It has been shown that the inhalation of toluene in rats can cause neuronal apoptosis in the central nervous system. However, the cellular and molecular effects of toluene directly on astrocytes are relatively unknown. We used primary cultures of astrocytes isolated from the neonatal rat cortex as a model to study the toluene effects on cell outcome and associated signal transduction pathways using immunostaining and Western blotting. We observed that acute toluene exposure significantly induced caspase-dependent cell apoptosis and transiently stimulated the activation of p42/44 mitogen-activated protein kinase (MAPK) in the primary astrocytes. Interestingly, the inhibition of the p42/44 MAPK signaling cascade by PD98059 in conjunction with the toluene treatment evoked more cellular apoptosis than toluene alone, suggesting that the toluene-induced transient MAPK activation may play a role in promoting cell survival during the toluene exposure.
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279
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Ma W, Farrukh Nizam M, Grewal RP. X-linked Charcot-Marie-Tooth disease caused by a novel point mutation in the connexin-32 gene. Neurol Sci 2002; 23:195-7. [PMID: 12536289 DOI: 10.1007/s100720200061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We report the clinical and electrophysiological findings of a patient with X-linked Charcot-Marie-Tooth disease and a novel point mutation in the connexin-32 gene. A 31-year-old man presented with a 5 year history of progressive imbalance and distal weakness in his legs. Electrophysiological studies confirmed an asymmetric, predominantly axonal sensorimotor neuropathy with some demyelinating features. Genetic testing revealed a G/A transition (Ala40Thr) in a conserved transmembrane region of the connexin-32 gene.
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280
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Tao X, Ma W, Zhang T, Zhao J. Efficient Photooxidative Degradation of Organic Compounds in the Presence of Iron Tetrasulfophthalocyanine under Visible Light Irradiation. Angew Chem Int Ed Engl 2002; 40:3014-6. [PMID: 12203633 DOI: 10.1002/1521-3773(20010817)40:16<3014::aid-anie3014>3.0.co;2-m] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2001] [Revised: 04/09/2001] [Indexed: 11/11/2022]
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281
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Ma W, Yang M, Wang J, Qi R, Ren L. Treatment of antibiotics wastewater utilizing successive hydrolysis, denitrification and nitrification. ENVIRONMENTAL TECHNOLOGY 2002; 23:685-694. [PMID: 12118620 DOI: 10.1080/09593330.2002.9619253] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A process consisting of anaerobic hydrolysis, denitrification, and oxidation/nitrification was proposed for simultaneous removal of carbon and nitrogen from terramycin crystallizing mother solution (TCMS), and its performance was investigated by treating diluted TCMS in a lab-scale continuous flow column system. Direct denitrification-nitrification of diluted TCMS produced a significant residual of nitrate and nitrite, which disappeared 44 days after startup of anaerobic hydrolysis column. The electron donors available to denitrification were increased by 6 times after diluted TCMS was treated in the hydrolysis column under an HRT of 2.5 h or longer. The reaction rates of organics decomposition, nitrification, and denitrification were also significantly increased due to reduction of terramycin and decomposition of complicated molecules to small molecules during anaerobic hydrolysis. The specific denitrification rate and nitrification rate increased from 0.033 d(-1) and 0.01 d(-1) to 0.045 d(-1) and 0.021 d(-1) respectively after diluted TCMS (dilution ratio: 1:4) was hydrolyzed in anaerobic hydrolysis column at a hydraulic retention time (HRT) of 4 h.
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282
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Baldus S, Eiserich JP, Mani A, Castro L, Figueroa M, Chumley P, Ma W, Tousson A, White CR, Bullard DC, Brennan ML, Lusis AJ, Moore KP, Freeman BA. Endothelial transcytosis of myeloperoxidase confers specificity to vascular ECM proteins as targets of tyrosine nitration. J Clin Invest 2001; 108:1759-70. [PMID: 11748259 PMCID: PMC209464 DOI: 10.1172/jci12617] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Nitrotyrosine formation is a hallmark of vascular inflammation, with polymorphonuclear neutrophil-derived (PMN-derived) and monocyte-derived myeloperoxidase (MPO) being shown to catalyze this posttranslational protein modification via oxidation of nitrite (NO(2)(-)) to nitrogen dioxide (NO(2)(*)). Herein, we show that MPO concentrates in the subendothelial matrix of vascular tissues by a transcytotic mechanism and serves as a catalyst of ECM protein tyrosine nitration. Purified MPO and MPO released by intraluminal degranulation of activated human PMNs avidly bound to aortic endothelial cell glycosaminoglycans in both cell monolayer and isolated vessel models. Cell-bound MPO rapidly transcytosed intact endothelium and colocalized abluminally with the ECM protein fibronectin. In the presence of the substrates hydrogen peroxide (H(2)O(2)) and NO(2)(-), cell and vessel wall-associated MPO catalyzed nitration of ECM protein tyrosine residues, with fibronectin identified as a major target protein. Both heparin and the low-molecular weight heparin enoxaparin significantly inhibited MPO binding and protein nitrotyrosine (NO(2)Tyr) formation in both cultured endothelial cells and rat aortic tissues. MPO(-/-) mice treated with intraperitoneal zymosan had lower hepatic NO(2)Tyr/tyrosine ratios than did zymosan-treated wild-type mice. These data indicate that MPO significantly contributes to NO(2)Tyr formation in vivo. Moreover, transcytosis of MPO, occurring independently of leukocyte emigration, confers specificity to nitration of vascular matrix proteins.
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283
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Zhang J, Wang Y, Ma W. [Clinical application of narcotic analgesics in patients with burn and plastic surgery]. ZHONGHUA SHAO SHANG ZA ZHI = ZHONGHUA SHAOSHANG ZAZHI = CHINESE JOURNAL OF BURNS 2001; 17:351-3. [PMID: 11859613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the effects of narcotic analgesics (opioids) on the patients with burn and plastic surgery. METHODS Retrospective statistical analysis was carried out in 452 patients with burn and plastic surgery in terms of the clinical signs of pain, the number of the patients who used the drug, the kinds of the drugs used, the doses and the number of use each day. RESULTS Inappropriate and insufficient application of narcotic analgesics was common in the past due to our incomplete knowledge of the importance of postburn and post-operative pain in patients with burn and plastic surgery, and also confused concepts of the pain and misuse of opioids, often leading to insufficient analgesia. CONCLUSION Much attention should be paid to navcotic analgesia in patients with burn plastic surgery. Some measures were suggested.
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284
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Wu Z, Li L, Ma W, Yu Y, Chen Y. [Study on the intestinal microbial colonization resistance in patients with chronic severe hepatitis]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2001; 9:329-30. [PMID: 11782296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To investigate the changes of microbial colonization resistance of the bowel in patients with chronic severe hepatitis. METHODS The fecal flora bifidobacteria, enterobacteriaceae, enterococci, and yeasts of subjects (chronic severe hepatitis, chronic hepatitis, and healthy volunteers) were quantitatively and qualitatively analyzed by Mitsuoka's methods. While the ratio of bifidobacterium to enterobacteriaceae ( B/E ratio ) was calculated. RESULTS The number of bifidobacteria and the B/E ratio in chronic severe hepatitis group was significantly deceased compared with that of the control group (P<0.001). The number of enterobacteriaceae and yeasts was significantly increased compared with that of control group (P<0.001 and P<0.01, respectively). CONCLUSIONS The results suggest that the intestinal microbial colonization resistance in patients with chronic severe hepatitis is seriously impaired.
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285
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Zhang D, Fu M, Ma W, Chen D. Fluorescent determination of noradrenaline and dopamine derivatized with Cy5 in capillary electrophoresis. ANAL SCI 2001; 17:1331-3. [PMID: 11759519 DOI: 10.2116/analsci.17.1331] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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286
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Ma W, Cui W, Lin Q. Improved immnunophenotyping of lymphocytes in bronchoalveolar lavage fluid (BALF) by flow cytometry. Clin Chim Acta 2001; 313:133-8. [PMID: 11694250 DOI: 10.1016/s0009-8981(01)00664-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The immnunophenotyping of lymphocytes in bronchoalveolar lavage fluid (BALF) is of particular importance in the differential diagnosis of interstitial lung disorders. The standard method of lymphocyte phenotyping is peroxidase-anti-peroxidase technique (PAP). However, it was time-consuming and experience-dependent. Flow cytometric (FCM) analysis of BALF lymphocytes was introduced to overcome these disadvantages. Unfortunately, when the number of cells counted was small, FCM could not distinguish lymphocytes from other cells and particles in BALF by light scattering. METHODS We established a tri-color flow cytometric approach to phenotyping of lymphocytes in BALF. FITC-CD45/PE-CD14 antibodies were used to gate lymphocytes and exclude other contamination. Propidium iodide (PI) was introduced to distinguish lymphocytes from debris. Forty-three BALF species were tested by flow cytometer as well as peripheral blood as a control group by conventional PAP method. RESULTS The variation of FCM (CV<1.0%) was much lower that that of PAP method (CV>9.8%). Meanwhile, we found that BALF had more clinical significance than peripheral blood in T subset analysis (p<0.01). There were characteristic changes in some lung diseases. Both CD3 and CD4 were significantly increased with decreasing CD8 in sarcoidosis (n=14). Idiopathic pulmonary fibrosis (n=16) demonstrated the reverse tendency: CD8 rose but both CD3 and CD4 dropped. As for lung cancer (n=7), CD3 was normal but the CD4/CD8 ratio declined. Tuberculosis of the lungs (n=6) showed a normal CD3, CD4 and CD8. CONCLUSIONS The high precision and reliability of tri-color flow cytometric approach to phenotyping of lymphocytes in BALF suggested that it should be used as a routine test, especially of BALF, which was often contaminated by inorganic particles.
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287
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Ma W, Tan J, Matsumoto H, Robert B, Abrahamson DR, Das SK, Dey SK. Adult tissue angiogenesis: evidence for negative regulation by estrogen in the uterus. Mol Endocrinol 2001; 15:1983-92. [PMID: 11682628 DOI: 10.1210/mend.15.11.0734] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Increased uterine vascular permeability and angiogenesis are two major events of embryo implantation and placentation during pregnancy. These latter processes require coordinated, uterine-specific interactions between progesterone (P4) and estrogen (E) signaling. Although roles of these steroids have long been suspected, definitive functions of E and/or P4 in uterine angiogenesis still remain elusive. We have therefore exploited the availability of reporter and mutant mice to explore the regulation of angiogenesis in response to steroid hormonal changes in vivo. We present here molecular, genetic, physiological, and pharmacological evidence that E and P4 have different effects in vivo: E promotes uterine vascular permeability but profoundly inhibits angiogenesis, whereas P4 stimulates angiogenesis with little effect on vascular permeability. These effects of E and P4 are mediated by differential spatiotemporal expression of proangiogenic factors in the uterus.
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MESH Headings
- Animals
- Endothelial Growth Factors/genetics
- Endothelial Growth Factors/metabolism
- Estradiol/analogs & derivatives
- Estradiol/metabolism
- Estradiol/pharmacology
- Estrogen Antagonists/pharmacology
- Estrogen Receptor alpha
- Female
- Fulvestrant
- Hormone Antagonists/pharmacology
- Lymphokines/drug effects
- Lymphokines/genetics
- Lymphokines/metabolism
- Male
- Mice
- Mice, Mutant Strains
- Mifepristone/pharmacology
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/physiology
- Progesterone/metabolism
- Progesterone/pharmacology
- Receptor Protein-Tyrosine Kinases/drug effects
- Receptor Protein-Tyrosine Kinases/genetics
- Receptor Protein-Tyrosine Kinases/metabolism
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Receptors, Growth Factor/drug effects
- Receptors, Growth Factor/genetics
- Receptors, Growth Factor/metabolism
- Receptors, Prolactin/genetics
- Receptors, Prolactin/metabolism
- Receptors, Vascular Endothelial Growth Factor
- Uterus/blood supply
- Uterus/drug effects
- Uterus/physiology
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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288
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Ma W. [A brief history of dermatoglyphics in China] (Chi). ZHONGHUA YI SHI ZA ZHI (BEIJING, CHINA : 1980) 2001; 16:155-8. [PMID: 11612065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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289
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Zhang L, Xing GQ, Barker JL, Chang Y, Maric D, Ma W, Li BS, Rubinow DR. Alpha-lipoic acid protects rat cortical neurons against cell death induced by amyloid and hydrogen peroxide through the Akt signalling pathway. Neurosci Lett 2001; 312:125-8. [PMID: 11602326 DOI: 10.1016/s0304-3940(01)02205-4] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Substantial evidence suggests that the accumulation of beta-amyloid (Abeta)-derived peptides contributes to the aetiology of Alzheimer's disease (AD) by stimulating formation of free radicals. Thus, the antioxidant alpha-lipoate, which is able to cross the blood-brain barrier, would seem an ideal substance in the treatment of AD. We have investigated the potential effectiveness of alpha-lipoic acid (LA) against cytotoxicity induced by Abeta peptide (31-35) (30 microM) and hydrogen peroxide (H(2)O(2)) (100 microM) with the cellular 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) reduction and fluorescence dye propidium iodide assays in primary neurons of rat cerebral cortex. We found that treatment with LA protected cortical neurons against cytotoxicity induced by Abeta or H(2)O(2). In addition, LA-induced increase in the level of Akt in the neurons was observed by Western blot. The LA-induced neuroprotection and Akt increase were attenuated by pre-treatment with the phosphatidylinositol 3-kinase inhibitor, LY294002 (50 microM). Our data suggest that the neuroprotective effects of the antioxidant LA are partly mediated through activation of the PKB/Akt signaling pathway.
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290
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Li BS, Sun MK, Zhang L, Takahashi S, Ma W, Vinade L, Kulkarni AB, Brady RO, Pant HC. Regulation of NMDA receptors by cyclin-dependent kinase-5. Proc Natl Acad Sci U S A 2001; 98:12742-7. [PMID: 11675505 PMCID: PMC60124 DOI: 10.1073/pnas.211428098] [Citation(s) in RCA: 210] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2001] [Indexed: 11/18/2022] Open
Abstract
Members of the N-methyl-d-aspartate (NMDA) class of glutamate receptors (NMDARs) are critical for development, synaptic transmission, learning and memory; they are targets of pathological disorders in the central nervous system. NMDARs are phosphorylated by both serine/threonine and tyrosine kinases. Here, we demonstrate that cyclin dependent kinase-5 (Cdk5) associates with and phosphorylates NR2A subunits at Ser-1232 in vitro and in intact cells. Moreover, we show that roscovitine, a selective Cdk5 inhibitor, blocks both long-term potentiation induction and NMDA-evoked currents in rat CA1 hippocampal neurons. These results suggest that Cdk5 plays a key role in synaptic transmission and plasticity through its up-regulation of NMDARs.
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291
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Zhang C, Patel R, Eiserich JP, Zhou F, Kelpke S, Ma W, Parks DA, Darley-Usmar V, White CR. Endothelial dysfunction is induced by proinflammatory oxidant hypochlorous acid. Am J Physiol Heart Circ Physiol 2001; 281:H1469-75. [PMID: 11557534 DOI: 10.1152/ajpheart.2001.281.4.h1469] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The myeloperoxidase (MPO)-derived oxidant hypochlorous acid (HOCl) plays a role in tissue injury under inflammatory conditions. The present study tests the hypothesis that HOCl decreases nitric oxide (NO) bioavailability in the vasculature of Sprague-Dawley rats. Aortic ring segments were pretreated with HOCl (1-50 microM) followed by extensive washing. Endothelium-dependent relaxation was then assessed by cumulative addition of acetylcholine (ACh) or the calcium ionophore A23187. HOCl treatment significantly impaired both ACh- and A23187-mediated relaxation. In contrast, endothelium-independent relaxation induced by sodium nitroprusside was unaffected. The inhibitory effect of HOCl on ACh-induced relaxation was reversed by exposure of ring segments to L-arginine but not D-arginine. In cellular studies, HOCl did not alter endothelial NO synthase (NOS III) protein or activity, but inhibited formation of the NO metabolites nitrate (NO3(-) and nitrite (NO2(-). The reduction in total NO metabolite production in bovine aortic endothelial cells was also reversed by addition of L-arginine. These data suggest that HOCl induces endothelial dysfunction via modification of L-arginine.
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292
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Ma W, Zheng WH, Powell K, Jhamandas K, Quirion R. Chronic morphine exposure increases the phosphorylation of MAP kinases and the transcription factor CREB in dorsal root ganglion neurons: an in vitro and in vivo study. Eur J Neurosci 2001; 14:1091-104. [PMID: 11683901 DOI: 10.1046/j.0953-816x.2001.01731.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Tolerance to opiates reduces their effectiveness in the treatment of severe pain. Although the mechanisms are unclear, overactivity of pro-nociceptive systems has been proposed to contribute to this phenomenon. We have reported that the development of morphine tolerance significantly increased calcitonin-gene-related-peptide-like immunoreactivity (CGRP-IR) in primary sensory afferents of the spinal dorsal horn, suggesting that changes in pain-related neuropeptides in the dorsal root ganglion (DRG) neurons may be involved (Menard et al., 1996, J. Neurosci., 16, 2342-2351). Recently, we have shown that repeated morphine treatments induced increases in CGRP- and substance P (SP)-IR in cultured DRG, mimicking the in vivo effects (Ma et al., 2000, Neuroscience, 99, 529-539). In this study, we investigated the intracellular signal transduction pathways possibly involved in morphine-induced increases in CGRP- and SP-IR in DRG neurons. Repeated morphine exposure (10-20 microm) for 6 days increased the number of neurons expressing phosphorylated (p) mitogen-activated protein (MAP) kinases, including the extracellular signal-regulated kinase (pERK), c-jun N-terminal kinase (pJNK) and P38 (pP38 MAPK). The number of neurons expressing phosphorylated cAMP responsive element binding protein (pCREB) was also markedly increased in morphine-exposed cultured DRG neurons. pERK-, pP38-, pJNK- and pCREB-IR were colocalized with CGRP-IR in cultured DRG neurons. Naloxone effectively blocked these actions of morphine, whereas a selective MEK1 inhibitor, PD98059, inhibited the morphine-induced increase in the phosphorylation of ERK and CREB, and the expression of CGRP and SP. Moreover, in morphine-tolerant rats, the number of pCREB-, CGRP- and SP-IR neurons in the lumbar DRG was also significantly increased. These in vitro and in vivo data suggest that the phosphorylation of MAP kinases and CREB plays a role in the morphine-induced increase in spinal CGRP and SP levels in primary sensory afferents, contributing to the development of tolerance to opioid-induced analgesia.
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293
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Wlaschek M, Tantcheva-Poór I, Naderi L, Ma W, Schneider LA, Razi-Wolf Z, Schüller J, Scharffetter-Kochanek K. Solar UV irradiation and dermal photoaging. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2001; 63:41-51. [PMID: 11684450 DOI: 10.1016/s1011-1344(01)00201-9] [Citation(s) in RCA: 291] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The skin is increasingly exposed to ambient UV-irradiation thus increasing risks for photooxidative damage with long-term detrimental effects like photoaging, characterized by wrinkles, loss of skin tone and resilience. Photoaged skin displays alterations in the cellular component and extracellular matrix with accumulation of disorganized elastin and its microfibrillar component fibrillin in the deep dermis and a severe loss of interstitial collagens, the major structural proteins of the dermal connective tissue. The unifying pathogenic agents for these changes are UV-generated reactive oxygen species (ROS) which deplete and damage non-enzymatic and enzymatic antioxidant defense systems of the skin. As well as causing permanent genetic changes, ROS activate cytoplasmic signal transduction pathways in resident fibroblasts that are related to growth, differentiation, senescence and connective tissue degradation. This review focuses on the role of UV-induced ROS in the photodamage of the skin resulting in clinical and biochemical characteristics of photoaging. In addition, the relationship of photoaging to intrinsic aging of the skin will be briefly discussed. A decrease in the overall ROS load by efficient sunscreens or other protective agents may represent promising strategies to prevent or at least minimize ROS-induced photoaging.
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294
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Ma W, Wlaschek M, Tantcheva-Poór I, Schneider LA, Naderi L, Razi-Wolf Z, Schüller J, Scharffetter-Kochanek K. Chronological ageing and photoageing of the fibroblasts and the dermal connective tissue. Clin Exp Dermatol 2001; 26:592-9. [PMID: 11696063 DOI: 10.1046/j.1365-2230.2001.00905.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In recent years, the exposure of human skin to environmental and artificial UV irradiation has increased dramatically. This is due not only to increased solar UV irradiation as a consequence of stratospheric ozone depletion, but also to inappropriate social behaviour with the use of tanning salons still being very popular in the public view. Besides this, leisure activities and a lifestyle that often includes travel to equatorial regions add to the individual annual UV load. In addition to the common long-term detrimental effects such as immunosuppression and skin cancer, the photo-oxidative damage due to energy absorption of UV photons in an oxygenized environment leads to quantitative and qualitative alterations of cells and structural macromolecules of the dermal connective tissue responsible for tensile strength, resilience and stability of the skin. The clinical manifestations of UV/reactive oxygen species (ROS)-induced disturbances result in photoaged skin with wrinkle formation, laxity, leathery appearance as well as fragility, impaired wound healing capacities and higher vulnerability. Strategies to prevent or at least minimize ROS-induced photo-ageing and intrinsic ageing of the skin necessarily include protection against UV irradiation and antioxidant homeostasis.
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295
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Xia C, Ma W, Wang F, Liu M. Identification of a prostate-specific G-protein coupled receptor in prostate cancer. Oncogene 2001; 20:5903-7. [PMID: 11593396 DOI: 10.1038/sj.onc.1204803] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2001] [Revised: 06/26/2001] [Accepted: 07/05/2001] [Indexed: 11/09/2022]
Abstract
Membrane receptors coupled to heterotrimeric G-proteins play an essential role in the transmission of signals from the extracellular environment to the cytoplasm of the cell. A wide variety of external stimuli, including neurotransmitters, hormones, phospholipids, photons, odorants, taste ligands, and growth factors, can activate specific members of the G-protein coupled receptors (GPCRs). Besides essential functions in fully differentiated cells and tissues, GPCRs are also involved in embryogenesis, tissue regeneration, cell growth stimulation, and cell proliferation. In this study, we identified a novel prostate-specific G-protein coupled receptor that interacts with Galpha(12) in our yeast two-hybrid assays. The expression of the receptor protein is highly restricted to human prostate tissues using multiple-tissue Northern blot analysis, and tissue expression array. Furthermore, the expression of prostate-specific receptor is increased significantly in prostate tumors in comparison with the matched normal prostate tissues using PCR and Southern blot analysis, suggesting a potential role of this tissue-specific G-protein coupled receptor in prostate cancer development.
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296
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Lozanoff S, Johnston J, Ma W, Jourdan-Le Saux C. Immunohistochemical localization of Pax2 and associated proteins in the developing kidney of mice with renal hypoplasia. J Histochem Cytochem 2001; 49:1081-97. [PMID: 11511678 DOI: 10.1177/002215540104900903] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Pax2 has been identified as a key regulatory protein associated with renal developmental malformations. The purpose of this study was to determine whether Pax2 protein expression, and that of other proteins important for normal renal development, is abnormally distributed in the prenatal kidney of the Brachyrrhine (Br) mouse that displays heritable renal hypoplasia. Embryonic 3H1 +/+ and Br/Br mice were collected between E11.0 and E18.0. Routine light microscopy and immunohistochemical analysis using antibodies to Pax2, E-cadherin, fibronectin, laminin, and Type IV collagen were applied to sequential tissue sections. E-cadherin stained consistently in the renal tubules of both normal and mutant animals. Whereas the initial expression of Pax2 corresponded between normal and mutant kidneys, it became progressively limited to the nephrogenic zone in +/+ animals, while distributing erratically in the Br/Br kidney. Fibronectin was not expressed in the normal nephrogenic zone but remained abundantly distributed throughout the Br/Br kidney. Luminin and Type IV collagen staining revealed a deficiency in renal vasculature formation in Br/Br kidneys. Results suggest that initial morphological differentiation occurs normally in the Br kidney but that subsequent nephric formation is associated with abnormal distribution of Pax2 and ECM proteins. (J Histochem Cytochem 49:1081-1097, 2001)
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297
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Yang Z, Zhu T, Ma G, Yin H, Qian W, Zhang F, Cao K, Ma W. Apolipoprotein E polymorphism in the early onset of coronary heart disease. Chin Med J (Engl) 2001; 114:983-5. [PMID: 11780396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To assess the relationship between apolipoprotein E (apoE) polymorphism and the early onset of coronary heart disease (CHD) and the effect of apoE on lipids and lipoproteins in healthy Chinese subjects. METHODS Sixty-eight patients with CHD younger than 55 years (CHD1), 136 patients with CHD older than 65 years (CHD2), and 136 healthy subjects were enrolled, and their plasma levels of triglyceride (TG), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) were determined. The apoE genotypes were identified by polymerase chain reaction-restriction fragment length polymorphism. RESULTS apoE 3/4 genotype and E4 allele frequency in the CHD1 group were higher than those in the CHD2 group and healthy subjects, while no differences were found between CHD2 and healthy subjects. Meanwhile, the plasma levels of TC and low density lipoprotein cholesterol (LDL-C) were higher in the CHD2 group than in both CHD1 group and healthy subjects. Each apoE isoprotein has variable TC and LDL-C levels that is E2 (E2/2 + E2/3) < E3(E3/3) < E4(E4/4 + E3/4). CONCLUSION apoE is one of the genetic factors that affect TC and LDL-C levels, and apoE 4 has a very close relation to CHD, suggesting that apoE 4 is an independent genetic factor of the early onset of CHD.
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298
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Shaffer KM, Lin HJ, Maric D, Pancrazio JJ, Stenger DA, Barker JL, Ma W. The use of GABA(A) receptors expressed in neural precursor cells for cell-based assays. Biosens Bioelectron 2001; 16:481-9. [PMID: 11544042 DOI: 10.1016/s0956-5663(01)00162-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
GABA(A) receptors are known targets for certain classes of environmental neurotoxins and pharmaceutical compounds. Since few neural cell lines express functional GABA(A) receptors, the capacity to rapidly screen for compounds that affect GABA(A) receptor function is presently limited. Previous work has demonstrated that rat neural precursor cells express functional GABA(A) receptors that can be monitored via Ca(2+) imaging. This study examined GABA(A) receptor subunit expression to determine whether GABA(A) receptor function and its interactions with neurotoxins is preserved after passaging. Neural precursor cells isolated from embryonic day 13 rat brain were expanded in serum-free medium containing basic fibroblast growth factor and passaged three times. Reverse transcription-polymerase chain reaction analysis demonstrated early expression of abundant mRNAs encoding various GABA(A) receptor subunits. Ca(2+) imaging showed that the highly proliferating precursor cells in passaged cultures maintained expression of functional GABA(A) receptors. In addition, we showed that trimethylolpropane phosphate, a neurotoxin generated during partial pyrolysis of a synthetic ester turbine engine lubricant, potently inhibited muscimol (GABA(A) receptor agonist) but not depolarization-induced cytosolic Ca(2+) increase. The findings of this study suggest that neural precursor cells may be well suited for the evaluation of certain environmental neurotoxins with convulsant activity. The potential use of neural precursor cells in high-throughput screens for compounds acting on GABA(A) receptors is discussed.
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299
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Li L, Yang Q, Huang J, Xu X, Chen Y, Chen Y, Ma W, Chen Z, Fu S. Treatment of hepatic failure with artificial liver support system. Chin Med J (Engl) 2001; 114:941-5. [PMID: 11780387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To assess the effectiveness of artificial liver support system (ALSS) treatment in patients with hepatic failure. METHODS 235 cases of hepatic failure were treated with ALSS in our hospital. All data were analyzed by SPSS. The effectiveness of ALSS treatment was compared according to different stages (i.e., early, middle and end stages). RESULTS 108 patients survived after therapy of ALSS. After each ALSS treatment, the liver function of these patients was greatly improved, the serum endotoxin and HBV-DNA concentrations were significantly decreased, and the serum concentration of aromatic amino acids (AAA) such as methionine decreased while the ratio of branched chain amino acids and aromatic amino acids (BCAA/AAA ratio) increased; patients treated with ALSS in the early or middle stages of disease had much higher survival rates than patients in the end stage of disease. CONCLUSION ALSS is a reliable therapy for advanced liver diseases and treatment at early or middle stages is appropriate.
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Ma W, Wang J, Liang C, Qi R, Yang M. [Anaerobic hydrolysis of terramycin crystallizing mother solution]. HUAN JING KE XUE= HUANJING KEXUE 2001; 22:41-4. [PMID: 11769226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The terramycin crystallizing mother solution contained high organics and high nitrogen. There were many kinds of bioinhibition in it but not enough electronic donor. Anaerobic hydrolysis of terramycin crystallizing mother solution was completed with up anarobic sludge bed in order to improve the biodegradability of wastewater and electronic donor in it. The variations of pH, COD, NH4+, and SO4(2-) were monitored. The COD removal was in a narrow range between 10% and 16.4% even when the HRT of the reactor was changed from 1.5 h to 6 h. pH increased because of formation of NH3 and reduction of SO4(2-). Most of SO4(2-) was reduced to S2- when the HRT was longer than 2 h. Batch experiments on hydrolyzed wastewater demonstrated that reaction rates of nitrification and denitrification increased by 90.9% and 45.2%, respectively.
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