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He XY, Merz G, Yang YZ, Pullakart R, Mehta P, Schulz H, Yang SY. Function of human brain short chain L-3-hydroxyacyl coenzyme A dehydrogenase in androgen metabolism. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1484:267-77. [PMID: 10760475 DOI: 10.1016/s1388-1981(00)00014-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Human brain short chain L-3-hydroxyacyl-CoA dehydrogenase (SCHAD) has been demonstrated to be a unique 3alpha-hydroxysteroid dehydrogenase (HSD) that can convert 5alpha-androstane-3alpha, 17beta-diol (3alpha-adiol) to dihydrotestosterone (DHT), whose affinity to the androgen receptor is 10(5)-fold higher than that of 3alpha-adiol. The catalytic efficiency of human SCHAD for this oxidative 3alpha-HSD reaction was estimated to be 164 min(-1) mM(-1), about 10-fold higher than that measured for the backward reaction. Thus, human brain SCHAD may function in androgen metabolism as a new kind of 3alpha-HSD by counteracting all other known 3alpha-HSDs, which would unidirectionally catalyze the reduction of DHT to the almost inactive 3alpha-adiol. Human SCHAD is identical to an amyloid-beta binding protein (ERAB) involved in Alzheimer's disease, which was previously reported to be associated with the endoplasmic reticulum. This protein is, in fact, localized in mitochondria, not endoplasmic reticulum, as evidenced by immunocytochemical studies and its noncleavable mitochondrial targeting sequence and lack of endoplasmic reticulum targeting signals or transmembrane segments. These results prompt the suggestion that the mitochondrion plays not only an essential role in the initial step of steroidogenesis, but also important roles in the intracellular homeostasis of sex steroid hormones. Northern blot analysis revealed that the human SCHAD gene is expressed in both gonadal and peripheral tissues including the prostate whose growth notably requires DHT, the most potent androgen. This study represents the first report of a 3alpha-HSD that could act to generate DHT from 3alpha-adiol and thereby maintain intracellular DHT levels. We propose that inhibitors of the 3alpha-HSD activity of human brain SCHAD could be useful for the treatment of benign prostatic hyperplasia and other disorders involving DHT metabolism, in combination with known inhibitors of steroid 5alpha-reductases.
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Dai H, Zhao J, Tan WS, Yang YZ. [Adaptation of insect cells(BTI-Tn-5B1-4) to serum-free culture]. SHENG WU GONG CHENG XUE BAO = CHINESE JOURNAL OF BIOTECHNOLOGY 2000; 16:232-4. [PMID: 10976335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The insect cells(BTI-Tn-5B1-4) were adapted, from the medium supplemented with 5% FBS, via 3%, 2%, 1% FBS, to grow in serum-free medium by sequential adaptation for about three months. After adaptation, the cells could successfully grow in the specifically designed serum-free medium with the viability above 90%. In addition, the effect of FBS concentrations and inoculum sizes on the insect cell growth was also investigated.
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He XY, Yang YZ, Schulz H, Yang SY. Intrinsic alcohol dehydrogenase and hydroxysteroid dehydrogenase activities of human mitochondrial short-chain L-3-hydroxyacyl-CoA dehydrogenase. Biochem J 2000; 345 Pt 1:139-43. [PMID: 10600649 PMCID: PMC1220740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The alcohol dehydrogenase (ADH) activity of human short-chain l-3-hydroxyacyl-CoA dehydrogenase (SCHAD) has been characterized kinetically. The k(cat) of the purified enzyme was estimated to be 2. 2 min(-1), with apparent K(m) values of 280 mM and 22microM for 2-propanol and NAD(+), respectively. The k(cat) of the ADH activity was three orders of magnitude less than the l-3-hydroxyacyl-CoA dehydrogenase activity but was comparable with that of the enzyme's hydroxysteroid dehydrogenase (HSD) activity for oxidizing 17beta-oestradiol [He, Merz, Mehta, Schulz and Yang (1999) J. Biol. Chem. 274, 15014-15019]. However, the k(cat) values of intrinsic ADH and HSD activities of human SCHAD were found to be two orders of magnitude less than those reported for endoplasmic-reticulum-associated amyloid beta-peptide-binding protein (ERAB) [Yan, Shi, Zhu, Fu, Zhu, Zhu, Gibson, Stern, Collison, Al-Mohanna et al. (1999) J. Biol. Chem. 274, 2145-2156]. Since human SCHAD and ERAB apparently possess identical amino acid sequences, their catalytic properties should be identical. The recombinant SCHAD has been confirmed to be the right gene product and not a mutant variant. Steady-state kinetic measurements and quantitative analyses reveal that assay conditions such as pH and concentrations of coenzyme and substrate do not account for the kinetic differences reported for ERAB and SCHAD. Rather problematic experimental procedures appear to be responsible for the unrealistically high catalytic rate constants of ERAB. Eliminating the confusion surrounding the catalytic properties of this important multifunctional enzyme paves the way for exploring its role(s) in the pathogenesis of Alzheimer's disease.
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Andersson U, Yang YZ, Björkhem I, Einarsson C, Eggertsen G, Gåfvels M. Thyroid hormone suppresses hepatic sterol 12alpha-hydroxylase (CYP8B1) activity and messenger ribonucleic acid in rat liver: failure to define known thyroid hormone response elements in the gene. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1438:167-74. [PMID: 10320799 DOI: 10.1016/s1388-1981(99)00036-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sterol 12alpha-hydroxylase (CYP 8B1) is a microsomal cytochrome P450 enzyme involved in bile acid synthesis that is of critical importance for the composition of bile acids formed in the liver. Thyroidectomy of rats caused a more than twofold increase of CYP8B1 and an almost fourfold increase of the corresponding mRNA levels compared to sham-operated rats. Treatment of intact rats with thyroxine caused a 60% reduction of enzyme activity and a 50% reduction of mRNA levels compared to rats injected with saline only. To investigate whether the promoter of the gene contains thyroid hormone response elements, the complete structure of the rat gene was defined. In similarity with the corresponding gene in mouse, rabbit and man, the rat gene was found to lack introns. It had an open reading frame containing 1500 bp corresponding to a protein of 499 amino acid residues. Although thyroid hormone decreased CYP8B1 activity and mRNA in vivo, no hitherto described thyroid hormone response elements were identified 1883 bases upstream of the transcription start site. It is concluded that rat CYP8B1 is regulated by thyroid hormone at the mRNA level. The results are discussed in relation to the structure of the gene coding for the enzyme.
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Hu CZ, Guo JJ, Yang YZ, Wang B, Tao Q, Zhou XY. [Investigation and analysis of pregnancy gingivitis in 700 pregnancy women]. SHANGHAI KOU QIANG YI XUE = SHANGHAI JOURNAL OF STOMATOLOGY 1999; 8:15-7. [PMID: 15048307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVE: To investigate the relation between the incidence of pregnancy gingivitis and pregnancy period as well as oral hygiene of pregnancy women. METHODS: From January 1995 to April 1996,700 pregnancy women were inquired and examinated clinically. RESULTS: The incidence of pregnancy gingivitis is 73.57%,of which,the incidence during the first trimester is 67.49%,the second 74.19% and the third,79.17%.The incidence of pregnancy epulis is 0.43%. CONCLUSION: The incidence of pregnancy gingivitis was increasing following the pregnancy month and sexual hormone.It was important of pregnancy women to consulting about oral hygiene.
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Gao N, Wang AJ, Yang YZ, Hu MX, Xie H. [Opioid receptor mediated modulation of intrahippocampal enkephalin induced cellular immune function]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1999; 51:106-10. [PMID: 11972184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
In the present work, the effect of intrahippocampal microinjection of opioid receptor antagonist naloxone on the enhancement of cellular immune responses induced by enkephalin was studied in rat. The results showed that (1) the proliferation activity of splenic lymphocytes stimulated by Con A and natural killer (NK) cell activity were decreased with microinjection of 1 microl lipopolysaccharide (LPS,50 ng/microl) into bilateral hippocampus; (2) the decrease of cellular immune responses induced by LPS could be inhibited by a preceding intrahippocampal injection of 1 microl met-enkephalin (10 microg/1 microl); (3) the enhancement of cellular immune responses induced by met-enkephalin could be blocked by an opioid receptor antagonist naloxon (10 microg/microl); and (4) cellular immune responses were also inhibited when naloxon was injected intrahippocampally alone. The above results suggest that the enhancement of cellular immune responses induced by enkephalin was mediated by opioid receptors in hippocampus.
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Wu Y, Yang YZ, Koenig RJ. Protein-protein interaction domains and the heterodimerization of thyroid hormone receptor variant alpha2 with retinoid X receptors. Mol Endocrinol 1998; 12:1542-50. [PMID: 9773977 DOI: 10.1210/mend.12.10.0178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Heterodimerization between thyroid hormone receptors (TRs) and retinoid X receptors (RXRs) is mediated by a weak dimerization interface within the DNA- binding domains (DBDs) and a strong interface within the C-terminal ligand- binding domains of the receptors. Previous studies have shown that the conserved ninth heptad in the TR ligand-binding domain appears to play a critical role in heterodimerization with RXR. However, despite lacking the full ninth heptad, TR variant alpha2 (TRv alpha2) can heterodimerize with RXR on specific direct repeat response elements, but not on palindromic elements or in solution. Two possibilities may account for TRv alpha2-RXR heterodimerization on direct repeats. First, the DBD of TRv alpha2 may play a critical role in heterodimerization with RXR. Second, a specific sequence within the unique C terminus of TRv alpha2 may promote the formation of TRv alpha2-RXR heterodimers. In this study, we used receptor chimeras in which the DBD of RXR was replaced by either the TR DBD or an unrelated DBD from the metalloregulatory transcription factor AMT1 to address the role of the DBD dimerization interface in TRv alpha2-RXR heterodimerization. Gel mobility shift analyses showed that whereas TR alpha1 formed heterodimers with these chimeras, TRv alpha2 failed to do so. Deletion of the unique C terminus of TRv alpha2 had only a marginal effect on heterodimerization with RXR. Mutations within the DBD dimerization interface abolished heterodimerization of full-length TRv alpha2 with RXR but only marginally affected heterodimerization of full-length TR alpha1 with RXR. These data support the hypothesis that the TR-RXR DBD dimerization interface plays a critical role in TRv alpha2-RXR heterodimerization. Additional data show that the amino acid residues that make direct TR-RXR contacts within the DBDs also may play a role in receptor monomer binding to DNA, since mutations within these residues severely impair this interaction.
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Liu GX, Yang YZ, Gu QB, Liu YH, Guo Q. Effects of taurine on L-type voltage-dependent Ca2+ channel in rat cardiomyocytes infected with coxsackievirus B3. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1998; 19:238-40. [PMID: 10375733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
AIM To study the effects of taurine on L-type voltage-dependent Ca2+ channel (VDCC) in adult rat cardiomyocytes infected with coxsackievirus B3 (CVB3). METHODS Whole-cell Ca2+ current of L-type VDCC was obtained by patch-clamp techniques. RESULTS The density of L-type Ca2+ current was 4.1 +/- 0.8 pA/pF in normal cardiomyocytes, but increased to 4.9 +/- 1.4 pA/pF with CVB3 infection. At 16 mmol.L-1, taurine decreased the density to 3.5 +/- 0.5 pA/pF in normal cardiomyocytes, and to 3.8 +/- 0.8 pA/pF in CVB3-infected cardiomyocytes. In addition, CVB3 shifted the membrane potential depolarizing to peak current (Vp) from 8 +/- 8 mV to 5 +/- 3 mV which could also be reverted to 8 +/- 4 mV by taurine. CONCLUSION Taurine inhibited the increase of Ca2+ inflow through L-type VDCC and normalized the decreased Vp induced by CVB3 infection. The effect of taurine on L-type VDCC was the mechanism of taurine attenuating the intracellular Ca2+ accumulation and abnormal electric activities induced by CVB3 infection.
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Melby PC, Yang YZ, Cheng J, Zhao W. Regional differences in the cellular immune response to experimental cutaneous or visceral infection with Leishmania donovani. Infect Immun 1998; 66:18-27. [PMID: 9423834 PMCID: PMC107853 DOI: 10.1128/iai.66.1.18-27.1998] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Infection with the protozoan Leishmania donovani can cause serious visceral disease or subclinical infection in humans. To better understand the pathogenesis of this dichotomy, we have investigated the host cellular immune response to cutaneous or visceral infection in a murine model. Mice infected in the skin developed no detectable visceral parasitism, whereas intravenous inoculation resulted in hepatosplenomegaly and an increasing visceral parasite burden. Spleen cells from mice with locally controlled cutaneous infection showed strong parasite-specific proliferative and gamma interferon (IFN-gamma) responses, but spleen cells from systemically infected mice were unresponsive to parasite antigens. The in situ expression of IFN-gamma, interleukin-4 (IL-4), IL-10, IL-12, and inducible nitric oxide synthase (iNOS) mRNAs was determined in the spleen, draining lymph node (LN), and cutaneous site of inoculation. There was considerably greater expression of IFN-gamma and IL-12 p40 mRNAs in the LN draining a locally controlled cutaneous infection than in the spleen following systemic infection. Similarly, there was a high level of IFN-gamma production by LN cells following subcutaneous infection but no IFN-gamma production by spleen cells following systemic infection. Splenic IL-4 expression was transiently increased early after systemic infection, but splenic IL-10 transcripts increased throughout the course of visceral infection. IL-4 and IL-10 mRNAs were also increased in the LN following cutaneous infection. iNOS mRNA was detected earlier in the LN draining a cutaneous site of infection compared to the spleen following systemic challenge. Thus, locally controlled cutaneous infection was associated with antigen-specific spleen cell responsiveness and markedly increased levels of IFN-gamma, IL-12, and iNOS mRNA in the draining LN. Progressive splenic parasitism was associated with an early IL-4 response, markedly increased IL-10 but minimal IL-12 expression, and delayed expression of iNOS.
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Liu Z, Yang YZ. [Advances in the study of indexes for periodontal diseases and their epidemiology: An overview]. SHANGHAI KOU QIANG YI XUE = SHANGHAI JOURNAL OF STOMATOLOGY 1997; 6:241-3. [PMID: 15160209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
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61
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Zhang GX, Pu SY, Yang YZ, Shen XD, Peng TQ, Chen HZ. Effect of losartan and captopril on expression of cardiac angiotensin II AT1 receptor mRNA in rats following myocardial infarction. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1997; 18:431-4. [PMID: 10322934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
AIM To study the effects of losartan (Los) and captopril (Cap) treatment on expression of cardiac angiotensin II (Ang) AT1 receptor mRNA in rats following myocardial infarction (MI). METHODS Twenty-four rats with MI after coronary ligation for 7 d were randomly divided into 4 groups: A) Cap in drinking water, ad lib (2 g.L-1), B) i.g. Los 10 mg.kg-1.d-1, C) i.g. Los 30 mg.kg-1.d-1, and D) placebo for 6 wk. Sham-ligation rats (group E) served as controls. The levels of cardiac Ang AT1 receptor mRNA expression in each group (n = 6) were examined by Dot blot using digoxigenin-labeled cDNA probes. RESULTS Comparing with reflected peak areas of hybridization positive signals in group D (2640 +/- 201 micron 2), the expression of the cardiac Ang AT1 receptor mRNA was much lower in the 3 treated groups (group A 1360 +/- 134 micron 2, group B 1430 +/- 244 micron 2, group C 1310 +/- 95 micron 2) (P < 0.01). But no difference was found between the 3 treated groups and sham-ligation group (1230 +/- 233 micron 2) (P > 0.05). CONCLUSION Los and Cap attenuated the increase of cardiac Ang AT1 receptor mRNA expression in rats following MI.
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Su YG, Yang YZ, Chen HZ. [Effect of taurine on calcium of cardiomyocytes]. SHENG LI KE XUE JIN ZHAN [PROGRESS IN PHYSIOLOGY] 1997; 28:157-9. [PMID: 11038714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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63
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Gu W, Yang YZ, He MX. [A study on combination therapy of Western and traditional Chinese medicine of acute viral myocarditis]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1996; 16:713-6. [PMID: 9772585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
UNLABELLED To investigate the combination therapy of Western and traditional Chinese medicine on treatment of acute viral myocarditis, 48 patients were randomly divided into 2 groups. The 1st group consisted of 30 patients, receiving the combination therapy of Western and traditional Chinese medicine, including Astragalus membranaceus, taurine, coenzyme Q10 and antiarrhythmics, while the 2nd group consisted of 18 patients, receiving the conventional therapy, including glucose-insulin-potassium (GIK), coenzyme Q10 and also antiarrhythmics. RESULTS The efficacy of combination therapy of western and traditional Chinese medicine was better than that of conventional therapy in improving the clinical manifestation, negative converting positive EVsRNA in peripheral leukocytes and controlling the premature beats. CONCLUSION The combination therapy of western and traditional Chinese medicine was an effective method in treating acute viral myocarditis.
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Yang YZ, Burgos-Trinidad M, Wu Y, Koenig RJ. Thyroid hormone receptor variant alpha2. Role of the ninth heptad in dna binding, heterodimerization with retinoid X receptors, and dominant negative activity. J Biol Chem 1996; 271:28235-42. [PMID: 8910441 DOI: 10.1074/jbc.271.45.28235] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Thyroid hormone receptors bind DNA with highest affinity as heterodimers with retinoid X receptors, and such heterodimers generally are thought to be the biological mediators of thyroid hormone action. An alternative splice product of the thyroid hormone receptor alpha gene, thyroid hormone receptor variant alpha2, does not bind thyroid hormone and functions as a weak dominant negative inhibitor of thyroid hormone action. Thyroid hormone receptor variant alpha2 is missing one-half of the ninth heptad, a region of the bona fide receptor thought to be important for heterodimerization with retinoid X receptors. The role of the ninth heptad in heterodimerization has been evaluated further. Thyroid hormone receptor variant alpha2-retinoid X receptor heterodimers form on a subset of direct repeat response elements but not on palindromic or inverted palindromic elements. Restoration of the missing ninth heptad sequence is critical for restoring heterodimerization on the palindromic DNA, but either the ninth heptad amino acids or a stretch of alanines is equally able to restore heterodimerization on the inverted palindrome. Thus, the role of the ninth heptad in heterodimerization differs on direct repeat, palindromic, and inverted palindromic response elements, suggesting that the protein-protein interactions differ on each of these elements. The dominant negative activity of thyroid hormone receptor variant alpha2 requires DNA binding, but the relatively weak nature of the dominant negative activity is only partially explained by the weak DNA binding.
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Wang AJ, Yang YZ, Wu YM, Xie H, Hu MX, Gao N, Hong J, Sun CL. [Effect of intrahippocampal microinjection of enkephalin on cellular immune function and brain IL-1 alpha gene expression in rat]. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 1996; 48:348-54. [PMID: 9389197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effect of intrahippocampal microinjection of enkephalin on cellular immune function and hippocampal IL-1 alpha gene expression was studied in rats. The results showed that: (1) The proliferation activity of splenic lymphocytes stimulated by Con A was significantly increased with microinjection of Leu-enkephalin 1 microliter (18 mmol/L) or Met-enkephalin 1 microliter (18 mmol/L) into bilateral hippocampus, but was inhibited by Lipopolysaccharide 1 microliter (50 ng/microliter). The proliferative response of splenic lymphocytes to Leu-enkephalin still persisted after bilateral adrenalectomy. Low doses of Leu- or Met-enkephalin (10(-10), 10(-11) mol/L) were also capable of causing proliferative activity of the Con A- stimulated cultured splenic lymphocytes in vitro. (2) Using RT-PCR technique, IL-1 alpha gene expression was detected in hippocampus 90 min after bilateral intrahippocampal injection of LPS. The LPS-induced IL-1 alpha gene expression in hippocampus could no longer be detected 30 min after microinjection of Met- or Leu-enkephalin into hippocampus. The above results suggested that intrahippocampal enkephalin might play an important role in neuro-immunomodulation by enhancing the inhibition of IL-1 alpha gene expression in hippocampal formation.
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Wan LX, Yang HP, Yang YZ. [Virus infection and atherosclerosis]. SHENG LI KE XUE JIN ZHAN [PROGRESS IN PHYSIOLOGY] 1996; 27:277-9. [PMID: 9772375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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67
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Guo Q, Peng TQ, Yang YZ. [Effect of Astragalus membranaceus on Ca2+ influx and coxsackie virus B3 RNA replication in cultured neonatal rat heart cells]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1995; 15:483-5. [PMID: 8580697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effect of Astragalus membranaceus (AM) on Ca2+ influx across the myocardial plasma membrane and coxsackie virus B3(CVB3)-RNA replication in cultured neonatal rat heart cells infected with CVB3 was investigated. It was found that the Ca2+ influx could be inhibited significantly (P < 0.01) by AM after infection of heart cells for 48 h. In addition, when the cultured heart cells infected with CVB3 and treated with AM for 48 h, the Ca2+ influx of infected heart cells also could be inhibited by AM (P < 0.05) and the amounts of CVB3-RNA in myocytes were significantly decreased than that in infected control group (P < 0.001). These phenomena suggested that AM could exert the effects of decreasing the secondary Ca2+ damages, and improving the abnormal myocardial electric activity, and inhibiting replication of CVB3-RNA in myocardium. Thus, it is a rational choice to treat patients with AM in viral myocarditis.
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Yang YZ, Subauste JS, Koenig RJ. Retinoid X receptor alpha binds with the highest affinity to an imperfect direct repeat response element. Endocrinology 1995; 136:2896-903. [PMID: 7789315 DOI: 10.1210/endo.136.7.7789315] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The regulation of gene expression by retinoids is mediated by two classes of receptors, retinoic acid receptors and retinoid X receptors (RXR). RXR can bind to specific target genes as homodimers, and these homodimers can activate gene expression in the presence of the ligand 9-cis-retinoic acid. A direct repeat of AGGTCA with a 1 base pair spacer (DR1) acts as a RXR homodimer response element in the presence of 9-cis-retinoic acid. However, it is not known if this represents the highest affinity binding site for the RXR homodimer. To investigate this question, we used a nonbiased strategy to isolate from a pool of random DNA those sequences that have the highest affinity for RXR alpha homodimers. The imperfect DR1 sequence 5'-GGGGTCAAAGGTCA displayed the highest in vitro binding affinity for RXR alpha homodimers. Transient transfection studies confirmed that this sequence is a more potent response element than is a perfect DR1 of either AGGTCA or GGGGTCA. The results also indicate that for RXR alpha homodimers, the receptor bound to the 5' half-site dislays different DNA binding specificity than that bound to the 3' half-site. Thus, DNA binding specificity is determined not only by the amino acid sequence of the protein but also by its protein-protein interactions and its position on the response element (5' vs. 3').
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Yang HP, Yang YZ, Zhou AR. [Application of antisense oligodeoxynucleotides on smooth muscle cells and endothelial cells]. SHENG LI KE XUE JIN ZHAN [PROGRESS IN PHYSIOLOGY] 1995; 26:259-62. [PMID: 8584898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Yang HP, Wang SN, Yang H, Zhou H, Yang YZ, Tang J, Zhou AR. [Study on hsp 70 gene level in cultured smooth muscle cells and aorta from SHR and WKY rats]. SHI YAN SHENG WU XUE BAO 1995; 28:31-5. [PMID: 7597867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Using nucleic hybridization, we investigated hsp 70 gene level on: 1. aorta on spontaneous hypertension rats (SHR); 2. cultured SHR and WKY smooth muscle cells (SMCs) induced by heat shock; 3. cultured SHR and WKY SMCs in 6 weeks and 3 months. The results indicated that hsp 70 mRNA increased in aorta of SHR (6 weeks), in cultured SHR SMCs as compared with WKY SMCs induced by heat shock (42 degrees C, 15 minutes), and in cultured SHR SMCs (6 weeks) as compared with WKY SMCs (6 weeks). Meanwhile, hsp 70 mRNA of cultured SHR SMCs in 6 weeks was higher than that in 3 months. We postulated that overexpression of hsp 70 of cultured SMCs and aorta of SHR in 6 weeks might be related with cellular proliferation during the development of hypertension and that the cultured SHR SMCs might be sensitive to heat shock.
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Yang YZ. [Effects of potassium oxalate with fluoride gel on dentin hypersensitivity]. SHANGHAI KOU QIANG YI XUE = SHANGHAI JOURNAL OF STOMATOLOGY 1995; 4:25-7. [PMID: 15160104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
This study observed the potassium oxalate including fluoride gel on the reduction of dentin hypersensitivity both in clinic and in laboratory.The results of the clinical treatment showed that this gel was statistically significant in reducing dentin hypersensitivity when the teeth treating by the gel for 4 minutes.The results of the scanning electric microscope(SEM) research indicated that the gel could create micro-globed particles deposition on the dentine surface.These particles have the ability to block the dentinal tubules and to decrease dentin hypersensitivity.In conclusion,this gel is an effective and safe topical agent for dentin hypersensitivity treatment.
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Li W, Crombach M, Schonian U, Yang YZ, Maisch B, Chen HZ. Detection of cytomegalovirus genome by in situ hybridization in paraffin embedded endomyocardial biopsy specimens of viral myocarditis. Chin Med J (Engl) 1994; 107:888-91. [PMID: 7882724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Cytomegalovirus (CMV) genes were detected by in situ hybridization in 25 Chinese patients with viral myocarditis (VMC). The positive hybridization signals were found in cardiomyocytes (6 cases, 24%), capillary endothelial cells (4 cases, 16%) and interstitial cells (7 cases, 28%). The difference between VMC and control group (16 cases died of brain trauma and 10 cases of congenital heart diseases was statistically significant. There was no definite pathomorphological relationship between the detection of CMV genes and myocardial lesions. The results suggest that CMV infection may be one of the causes of myocarditis and chronic stimulation of the immune system induced by CMV may be a possible pathogenesis of this disease.
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Peng TQ, Yang YZ, Kandolf R. [Effect and mechanism of Astragalus membranaceus on coxsackie B3 virus RNA in mice]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 1994; 14:664-6. [PMID: 7703635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Using Balb/c mice infected with Coxsackie virus B3 (CVB3) as a model, the effect of Astragalus membranaceus (AM) on CVB3-RNA has been observed in myocardial tissues of mice by RNA-RNA in situ hybridization with negative-strand RNA probes leballing with 35S and quantitative imaging analysis of positive hybridization signals. The mechanism of its effect on CVB3-RNA has also been investigated by induction with AM and detection of beta-interferon (beta-IFN). Results showed that the copy numbers of CVB3-RNA as well as the histologic necrotic sizes in myocardial tissues of AM treated infected mice were significantly smaller than that in infected normal saline treated mice (P < 0.01, P < 0.05) respectively, suggesting that AM could inhibit the replication of CVB3-RNA, but its effect on CVB3-RNA was not correlated with induction of beta-IFN.
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74
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Yang YZ, Little B, Meshnick SR. Alkylation of proteins by artemisinin. Effects of heme, pH, and drug structure. Biochem Pharmacol 1994; 48:569-73. [PMID: 8068044 DOI: 10.1016/0006-2952(94)90287-9] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Artemisinin and its derivatives are a promising new class of antimalarial agents containing an endoperoxide bridge. [14C]Artemisinin alkylated various proteins in vitro. Between 5 and 18% of added drug bound to hemoproteins such as catalase, cytochrome c, and hemoglobin. However, it did not react with heme-free globin. For catalase and hemoglobin, most of the drug reacted with the protein moiety rather than the heme. Artemisinin bound to human serum albumin (HSA) more efficiently at pH 8.6 than 7.4, more efficiently in Dulbecco's PBS than in Tris-HCl buffer, and better when HSA had been made fatty acid-free. Dihydroartemisinin also bound to HSA, whereas deoxyartemisinin, an inactive derivative, did not. There was no binding between DNA and artemisinin. These data provide insight into the mechanism of the reaction between artemisinin and proteins.
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75
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Rui T, Yang YZ, Zhou TS, Yang XY, Chen HZ. [Protective effect of captopril on cultured rat myocardial cells with anoxia and reoxygenation injury]. ZHONGGUO YAO LI XUE BAO = ACTA PHARMACOLOGICA SINICA 1994; 15:375-8. [PMID: 7801786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The effect of captopril (Cap) on electric activity of cultured rat myocardial cells under anoxia and reoxygenation was studied with standard microelectrode techniques. Results showed that anoxic solution caused lowerings of MDP, APA, and Vmax, and a shortening of APD50. All myocytes revealed multiform arrhythmias, and most cells stopped beating within 30 min, while only 40% of the cells exhibited arrhythmias but none stopped beating in the presence of 40 mg.L-1 under the same condition. During reoxygenation, most cells resumed beating in 10 min but some of these cells stopped beating again. The electric activities in rebeating cells during reoxygenation for 30 min were lower than those in normoxic cells. Cap (40 mg.L-1)-treated cells rebeat quickly after reoxygenation and no cell stopped beating any more, with parameters higher than those in untreated cells. These results demonstrate that Cap yields some beneficial effects on preventing anoxia and reoxygenation injury in cultured rat myocardial cells.
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