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Tang YL, Zhu YL, Liu Y, Wang YJ, Ma XL. Giant linear strain gradient with extremely low elastic energy in a perovskite nanostructure array. Nat Commun 2017; 8:15994. [PMID: 28665413 PMCID: PMC5497064 DOI: 10.1038/ncomms15994] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 05/18/2017] [Indexed: 11/09/2022] Open
Abstract
Although elastic strains, particularly inhomogeneous strains, are able to tune, enhance or create novel properties of some nanoscale functional materials, potential devices dominated by inhomogeneous strains have not been achieved so far. Here we report a fabrication of inhomogeneous strains with a linear gradient as giant as 106 per metre, featuring an extremely lower elastic energy cost compared with a uniformly strained state. The present strain gradient, resulting from the disclinations in the BiFeO3 nanostructures array grown on LaAlO3 substrates via a high deposition flux, induces a polarization of several microcoulomb per square centimetre. It leads to a large built-in electric field of several megavoltage per metre, and gives rise to a large enhancement of solar absorption. Our results indicate that it is possible to build up large-scale strain-dominated nanostructures with exotic properties, which in turn could be useful in the development of novel devices for electromechanical and photoelectric applications.
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Zhang CH, Yan BS, Xu BS, Ma XL, Yang Q, Liu Y, Song GM, Hu RM, Li P. [Study on feasibility of enhanced recovery after surgery combined with mobile microendoscopic discectomy-transforaminal lumbar interbody fusion in the treatment of lumbar spondylolisthesis]. ZHONGHUA YI XUE ZA ZHI 2017. [PMID: 28648000 DOI: 10.3760/cma.j.issn.0376-2491.2017.23.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the feasibility of enhanced recovery after surgery (ERAS) combined with mobile microendoscopic discectomy-transforaminal lumbar interbody fusion (MMED-TLIF) in the treatment of lumbar spondylolisthesis and its influence on postoperative rehabilitation. Methods: From October 1 2014 to July 1 2016 , a cohort of 52 patients with lumbar spondylolisthesis who received the program of ERAS-MMED-TLIF were retrospectively reviewed in Department of Minimally Invasive Spine Surgery, Tianjin Hospital.The primary outcomes include the operation time, intraoperative blood loss, length of hospital stay, VAS score (low back pain and leg pain) and Oswestry Disability Index (ODI) at different follow-up time and complication.The height of intervertebral space and fusion rate were also recorded as radiographic indicators. Results: All cases had an average follow-up of 12 months. The mean operative time was (115±30) min with a mean blood loss of (100±35) ml.Compared with preoperative condition, VAS score of low back pain (6.3±3.3 vs 3.5±2.3, P<0.05), VAS score of leg pain (7.1 ± 4.2 vs 3.1 ± 2.6, P<0.05) and the ODI disability index score (43.5±9.6 vs 20.9±7.3, P<0.05) at the postoperative 24 h were decreased and the difference was statistically significant.The mean hospitalized time were (4.9±1.3) days with mean postoperative hospital stay (2.1±1.2) days.Fusion rate was 92.31% (48/52) at the last follow-up time. Conclusion: ERAS combined with MMED-TLIF is feasible in the treatment of lumbar spondylolisthesis, which can significantly reduce intraoperative bleeding, shorten the total length of stay and postoperative hospital stay, improve postoperative pain and promote rapid rehabilitation of patients after operation without increasing the operation time and influencing the long-term effect, it can be applied in clinical practice.
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Zhang B, Wang J, Wu B, Oguzie EE, Luo K, Ma XL. Direct observation of atomic-scale origins of local dissolution in Al-Cu-Mg alloys. Sci Rep 2016; 6:39525. [PMID: 28000750 PMCID: PMC5175146 DOI: 10.1038/srep39525] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 11/23/2016] [Indexed: 11/20/2022] Open
Abstract
Atomistic chemical inhomogeneities are anticipated to induce dissimilarities in surface potentials, which control corrosion initiation of alloys at the atomic scale. Precise understanding of corrosion is therefore hampered by lack of definite information describing how atomistic heterogeneities regulate the process. Here, using high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) and electron energy loss spectroscopy (EELS) techniques, we systematically analyzed the Al20Cu2Mn3 second phase of 2024Al and successfully observed that atomic-scale segregation of Cu at defect sites induced preferential dissolution of the adjacent zones. We define an “atomic-scale galvanic cell”, composed of zones rich in Cu and its surrounding matrix. Our findings provide vital information linking atomic-scale microstructure and pitting mechanism, particularly for Al-Cu-Mg alloys. The resolution achieved also enables understanding of dealloying mechanisms and further streamlines our comprehension of the concept of general corrosion.
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Yang Z, Yuan ZZ, Ma JX, Ma XL. [Complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures: a meta-analysis]. ZHONGHUA YI XUE ZA ZHI 2016; 96:3833-3837. [PMID: 28057101 DOI: 10.3760/cma.j.issn.0376-2491.2016.47.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To make a systematic assessment of the complications of open reduction and internal fixation versus external fixation for unstable distal radius fractures. Method: A computer-based online search of PubMed, ScienceDirect, EMBASE, BIOSIS, Springer and Cochrane Library were performed.The randomized and controlled trials of open reduction and internal fixation versus external fixation for unstable distal radius fractures were collected.The included trials were screened out strictly based on the criterion of inclusion and exclusion.The quality of included trials was evaluated.RevMan 5.0 was used for data analysis. Result: A total of 17 studies involving 1 402 patients were included.There were 687 patients with open reduction and internal fixation and 715 with external fixation.The results of Meta-analysis indicated that there were statistically significant differences with regard to the postoperatively total complications, infection, malunion, tendon rupture (I2=8%, RR=0.77(95%CI 0.65-0.91, Z=3.10, P<0.05). There were no statistically significant differences observed between two approaches with respect to nounion, re-operation, complex regional pain syndrome, carpal tunnel syndrome, neurapraxia, tendonitis, painful hardware, scar(P>0.05). Conclusion: Postoperative complications are present in both open reduction and internal fixation and external fixation.Compared with external fixation, open reduction and internal fixation is lower in total complications postoperatively, infection and malunion, but external fixation has lower tendon rupture incidence.
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Chen JM, Zhou CJ, Ma XL, Guan DD, Yang LY, Yue P, Gong LP. [Abnormality of TOP2A expression and its gene copy number variations in neuroblastic tumors]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2016; 45:748-754. [PMID: 27821228 DOI: 10.3760/cma.j.issn.0529-5807.2016.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To detect TOP2A protein expression and gene copy number alterations, and to analyze related clinical and pathological implications in pediatric neuroblastic tumors (NT). Methods: Immunohistochemistry was used to detect TOP2A protein expression. Fluorescence in situ hybridization (FISH) was used to detect numerical aberrations of TOP2A. Results: TOP2A protein was expressed in 59.1%(52/88) of cases, which was associated with differentiation (P=0.006), Ki-67 index (P<0.01) and MKI (P=0.001). Twenty-eight cases (35.0%, 28/88) showed TOP2A gene amplification, which was correlated with the age (P<0.01), clinical stage (P=0.028), high risk group (P=0.001), Ki-67 index (P=0.040) and differentiation (P=0.014). Survival analysis showed that TOP2A expression was related to survival rate. Multivariate analyses showed that TOP2A expression was an independent predictor for poor prognosis (P=0.010). Conclusions: More than half of the cases show TOP2A expression, which is more likely associated with NB, high Ki-67 index and high MKI. Cases with TOP2A expression have shorter survivals and poorer prognosis. TOP2A amplification is seen in 35% and likely occurs in patients older than 18 months and at advanced INSS stages (Ⅲ and Ⅳ). As a target of the anthracycline-based adjuvant drugs, TOP2A test can be used to select patient with NT for the therapy.
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Xu YB, Tang YL, Zhu YL, Liu Y, Li S, Zhang SR, Ma XL. Misfit Strain Relaxation of Ferroelectric PbTiO 3/LaAlO 3 (111) Thin Film System. Sci Rep 2016; 6:35172. [PMID: 27725752 PMCID: PMC5057106 DOI: 10.1038/srep35172] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 09/20/2016] [Indexed: 11/09/2022] Open
Abstract
Ferroelectric thin films grown on high index substrates show unusual structural and switching dynamics due to their special strain states. Understanding the misfit relaxation behavior is crucial to facilitate the high index thin film growth with improved quality. In this paper, ferroelectric PbTiO3 thin films were grown on LaAlO3 (111) substrates by pulsed laser deposition technique. The microstructures were investigated by combinations of conventional and aberration-corrected transmission electron microscopy. Diffraction contrast analysis and high resolution imaging reveal that high density interfacial dislocations were distributed at the interfaces. These dislocations have mixed character with Burgers vectors of a <110> and line directions of <112>. The edge components of the dislocations, with the Burgers vectors parallel to the interface, accommodate the lattice mismatch and are the main contributor to the misfit relaxation of this system. The formation mechanism of these dislocations is proposed and discussed to elucidate the novel mismatch relaxation behavior of <111> oriented perovskite films.
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Lin HJ, Shi LP, Ma XL. [Long-term total parenteral nutrition therapy in an infant with all intestines removed after surgery: a case report]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2016; 54:709-10. [PMID: 27596089 DOI: 10.3760/cma.j.issn.0578-1310.2016.09.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Shao XH, Zheng SJ, Chen D, Jin QQ, Peng ZZ, Ma XL. Deformation twinning induced decomposition of lamellar LPSO structure and its re-precipitation in an Mg-Zn-Y alloy. Sci Rep 2016; 6:30096. [PMID: 27435638 PMCID: PMC4951811 DOI: 10.1038/srep30096] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 06/29/2016] [Indexed: 11/24/2022] Open
Abstract
The high hardness or yield strength of an alloy is known to benefit from the presence of small-scale precipitation, whose hardening effect is extensively applied in various engineering materials. Stability of the precipitates is of critical importance in maintaining the high performance of a material under mechanical loading. The long period stacking ordered (LPSO) structures play an important role in tuning the mechanical properties of an Mg-alloy. Here, we report deformation twinning induces decomposition of lamellar LPSO structures and their re-precipitation in an Mg-Zn-Y alloy. Using atomic resolution scanning transmission electron microscopy (STEM), we directly illustrate that the misfit dislocations at the interface between the lamellar LPSO structure and the deformation twin is corresponding to the decomposition and re-precipitation of LPSO structure, owing to dislocation effects on redistribution of Zn/Y atoms. This finding demonstrates that deformation twinning could destabilize complex precipitates. An occurrence of decomposition and re-precipitation, leading to a variant spatial distribution of the precipitates under plastic loading, may significantly affect the precipitation strengthening.
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Dong TT, Yu Q, Qing XR, Ma XL, Dong WW, Shi J, Li HG. Potential confounding factors in measurement of specific cell-free seminal mRNAs and microRNAs derived from human reproductive organs. Andrology 2016; 4:1010-1019. [PMID: 27368750 DOI: 10.1111/andr.12238] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 05/03/2016] [Accepted: 05/17/2016] [Indexed: 12/13/2022]
Abstract
Cell-free seminal RNA (cfs-RNA) is mixed transcripts derived from male reproductive organs, and is potential biomarker for the research and diagnosis of male reproductive-related diseases. However, some clinical factors, including age, asymptomatic Ureaplasma urealyticum (UU) infection, scrotal heat stress, abstinence period, and the storage condition of semen samples, may interfere with sperm parameters and the measurement of seminal biomarkers. Accordingly, this study was designed to evaluate the effect of above clinical factors on the measurement of cfs-RNA, aiming to lay a foundation for its research use and potential clinical application. Semen samples were collected according to the selected clinical factors. Cell-free seminal plasma was obtained by centrifugation and total RNA was extracted with TRIzol LS. Selective male reproductive organ-specific cfs-mRNAs and cfs-miRNAs were quantified by quantitative real-time PCR. The concentration and total amount of cfs-mRNAs and cfs-miRNAs in one ejaculate were calculated and compared. ACTB, DDX4 (testis-specific), WFDC9 (epididymis-specific), and miR-514a-3p (testis-specific) significantly increased after scrotal heat stress. SEMG1 (seminal vesicle-specific) showed declining tendency with the prolonged abstinence period. Age, asymptomatic UU infection, and the storage condition showed no significant impact on the measurement of cfs-RNA. These results indicate that scrotal heat stress significantly interfere with the selected cfs-RNA derived from the testis and epididymis, and abstinence period may affect the yield of cfs-mRNA from seminal vesicle, while other clinical factors has no significant impact on the measurement. Thus, heat exposure and abstinence period should be considered for the cfs-RNA measurement in its research or clinical application.
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Wen JX, Ma XL, Liu DL. [Significance of five symptoms scoring sheet in the clinical diagnosis of BPPV]. LIN CHUANG ER BI YAN HOU TOU JING WAI KE ZA ZHI = JOURNAL OF CLINICAL OTORHINOLARYNGOLOGY, HEAD, AND NECK SURGERY 2016; 30:784-787. [PMID: 29798053 DOI: 10.13201/j.issn.1001-1781.2016.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Indexed: 06/08/2023]
Abstract
Objective:To identify the validity of five symptoms scoring sheet that based on the patients who are suffering from benign paroxysmal positional vertigo(BPPV), and explore its effects and significance in the clinical diagnosis of BPPV.Method:A total of 484 patients with vertigo were included. All the patients were firstly assessed with five symptoms scoring sheet(repeated transient vertigo or aggravating vertigo during looking up, bending, getting out of bed, rolling over in bed and quick head movements) before being confirmed by Dix-Hallpike test and rolling test. Evaluating the predictive ability of this scoring sheet in the diagnosis of BPPV with ROC analysis.Result:According to the ROC analysis , the sensitivity and specificity were 95.4% and 80.3% respectively when the score >7, and an area under receiver operating characteristic curve(AUC) was 0.923.Conclusion:Five symptoms scoring sheet is useful and convenient in diagnosing BPPV, which can be used in BPPV screening and guide the vertigo patients to receive further test and treatment.
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Ou HJ, Huang G, Liu W, Ma XL, Wei Y, Zhou T, Pan ZM. Relationship of the APOA5/A4/C3/A1 gene cluster and APOB gene polymorphisms with dyslipidemia. GENETICS AND MOLECULAR RESEARCH 2015; 14:9277-90. [PMID: 26345861 DOI: 10.4238/2015.august.10.8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We determined the alleles of ten single nucleotide poly-morphisms (SNPs) in the APOA5/A4/C3/A1 gene cluster and in APOB in Han Chinese from Xinjiang Shihezi, China using MALDI-TOF mass spectrometry, and explored the correlation between these SNPs and dyslipidemia through a case-control study design with 250 pa-tients and 250 normal controls. All SNPs except for APOA5 rs2072560 conformed to Hardy-Weinberg equilibrium (all P > 0.05). APOA5 rs651821, APOA4 rs5104, APOC3 rs734104, and APOC3 rs5128 geno-type and allele frequencies were significantly different between groups (all P < 0.01). For rs651821, the risks of dyslipidemia for the CC or CC+CT genotypes were 9.917 or 1.859 times that of TT, and the risk of the C vs T allele was 2.027. For rs5104, the AG, GG, or AG+GG risks were 1.797, 1.861, and 1.809 times AA, and the G vs A risk was 1.427. For rs734104, the CT, CC, or CC+CT risks were 1.851, 2.570, and 1.958 times TT, and the C vs T risk was 1.610. For rs5128, the GC or CC+GC risks were 1.738 or 1.749 times GG, and the C vs G risk was 1.477. Compared with the wild-type haplotype TATG, the risks of dyslipidemia with CGCC, TGCC, or CATG haplotypes (odds ratios = 2.434, 1.503, and 2.740, respectively) were significantly higher. Our results suggested that these four SNPs were significantly associated with dyslipidemia in Xinjiang Shihezi Han Chinese, and might serve as risk factors for dyslipidemia. Individuals carrying the CGCC, TGCC, or CATG haplotypes were prone to dyslipidemia.
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Hu XB, Zhu YL, Sheng NC, Ma XL. The Wyckoff positional order and polyhedral intergrowth in the M3B2- and M5B3-type boride precipitated in the Ni-based superalloys. Sci Rep 2014; 4:7367. [PMID: 25482386 PMCID: PMC4258654 DOI: 10.1038/srep07367] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 11/20/2014] [Indexed: 11/09/2022] Open
Abstract
Ni-based single superalloys play a crucial role in the hottest parts of jet engines. However, due to the complex geometry and macro-segregation during the solidification process, the cast defect such as stray grains is inevitable. Therefore, the transient liquid phase (TLP) bonding which can join several small single crystalline castings together is gradually believed to be an effective method for improving the yields of production of the complex components. The melting point depressant element B is always added into the interlayer filler material. Consequently, borides including the M3B2 and M5B3 phase usually precipitate during the TLP bonding process. So a comprehensive knowledge of the fine structural characteristics of the borides is very critical for an accurate evaluation of the TLP bonding process. In this work, by means of the aberration-corrected transmission electron microscopy, we show, at an atomic scale, the Wyckoff positional order phenomenon of the metal atoms in the unit cell of M3B2- and M5B3-type boride. Meanwhile, the defect along the (001) plane of the above two types of boride are determined to be the polyhedral intergrowth with complex configurations.
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Jia HB, Ma JX, Ma XL, Yu JT, Feng R, Xu LY, Wang J, Xing D, Zhu SW, Wang Y. Estrogen alone or in combination with parathyroid hormone can decrease vertebral MEF2 and sclerostin expression and increase vertebral bone mass in ovariectomized rats. Osteoporos Int 2014; 25:2743-54. [PMID: 25074352 DOI: 10.1007/s00198-014-2818-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 07/22/2014] [Indexed: 12/28/2022]
Abstract
UNLABELLED The study is about the regulatory effects of estrogen and parathyroid hormone (PTH) on sclerostin, a protein that inhibits the Wnt/β-catenin pathway. The results indicate that estrogen may down-regulate sclerostin expression and that estrogen displays synergistic action with PTH. These results provide a new perspective on the relationship between estrogen and bone. PURPOSE To investigate whether estrogen can down-regulate SOST and MEF2 (myocyte enhancer factor 2) expression and whether co-treatment with estrogen and PTH has a stronger effect on suppressing SOST than PTH applied alone in ovariectomized rats. METHODS Forty-three-month-old virgin female Sprague-Dawley (SD) rats were ovariectomized and divided into four groups (n = 10). Another ten age-matched rats received sham operations as controls. After allowing 8 weeks for the development of vertebral osteopenia, the rats were administered the drug intervention. For this intervention, the estrogen group was subcutaneously injected with 17β-estradiol at 25 μg/kg body weight, the PTH group was injected with 80 μg/kg synthetic human PTH (1-34), and the co-treatment group was concurrently treated with PTH and estrogen at the above dosage. The OVX group and sham group were treated with vehicle. The drug treatment was conducted for 12 weeks. After the lumbar spine bone mineral density (BMD) was measured, the rats were sacrificed, and the lumbar spine and blood were collected for qPCR, Western blot, immunohistochemistry and other tests. RESULTS Estrogen can down-regulate MEF2 and sclerostin expression, and co-treatment with estrogen and PTH has a stronger effect on suppressing MEF2 and SOST mRNA than PTH alone. The co-treatment group displayed slightly higher bone mass and biomechanical properties than the PTH group, but the differences were not significant. CONCLUSIONS Estrogen appears to be a regulator of sclerostin, and the effect may involve suppressing MEF2s. Combined treatment with PTH and estrogen is not more beneficial for vertebral bone mass and strength than treatment with PTH alone in ovariectomized rats.
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Dang NN, Pang SG, Song HY, An LG, Ma XL. Filaggrin silencing by shRNA directly impairs the skin barrier function of normal human epidermal keratinocytes and then induces an immune response. ACTA ACUST UNITED AC 2014; 48:39-45. [PMID: 25493381 PMCID: PMC4288491 DOI: 10.1590/1414-431x20144047] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/28/2014] [Indexed: 01/25/2023]
Abstract
The objective of this study was to investigate whether a single defect in skin
barrier function simulated by filaggrin silencing could induce Th2-predominant
inflammation. Filaggrin gene expression was silenced in cultured normal human
epidermal keratinocytes (NHEKs) using small hairpin RNA (shRNA, GTTGGCTCAAGCATATTATTT).
The efficacy of silencing was confirmed by polymerase chain reaction (PCR) and
Western blotting. Filaggrin-silenced cells (LV group), shRNA control cells (NC
group), and noninfected cells (Blank group) were evaluated. The expression of
cornified cell envelope-related proteins, including cytokeratin (CK)-5, -10, -14,
loricrin, involucrin, and transglutaminase (TGM)-1, was detected by Western blotting.
Interleukins (IL)-2, IL-4, IL-5, IL-12p70, IL-13, and interferon-gamma (IFN-γ) were
detected by enzyme-linked immunosorbent assay (ELISA). After filaggrin was
successfully silenced by shRNA, the expressions of CK-5, -10, -14, involucrin, and
TGM-1 in NHEKs were significantly downregulated compared to the Blank and NC groups
(P<0.05 or P<0.01); only loricrin expression was markedly upregulated
(P<0.01). Filaggrin silencing also resulted in significant increases of IL-2,
IL-4, IL-5, and IL-13 (P<0.05 or P<0.01), and significant decreases of IL-12p70
and IFN-γ (P<0.01) compared with cells in the Blank and NC groups. Filaggrin
silencing impaired normal skin barrier function mainly by targeting the cornified
cell envelope. The immune response after filaggrin silencing was characterized by Th2
cells, mainly because of the inhibition of IFN-γ expression. Lack of filaggrin may
directly impair skin barrier function and then further induce the immune
response.
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Zhang L, Sun J, Zhang JQ, Yang M, Bai G, Ma XL. Expression and significance of molecular biomarkers in esophageal carcinoma in different nationalities patients in Xinjiang. GENETICS AND MOLECULAR RESEARCH 2014; 13:5413-25. [PMID: 25078598 DOI: 10.4238/2014.july.24.21] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This study aimed to explore some useful biomarkers to focus on the diagnosis and therapy response judgment in esophageal squamous cell carcinoma in Xinjiang. We used enzyme-linked immunosorbent method and immunohistochemistry to detect the expression of VEGF, EGFR, ES, HER-2, and NF-κBp in the serum and tissue with esophageal squamous cell carcinoma, and to analyze the relationship between biomarkers and clinical pathology and curative effects. Our findings were as follows: 1. The serum levels of VEGF and ES in Han patients were obviously higher than those of Uygur and Kazakh patients (P < 0.05). The VEGF positive rate in patients at a later clinical stage was higher than that of the patients at an earlier clinical stage (stages II-IV were 14.29, 50.00, and 50.00%, respectively, P < 0.05), meanwhile it was higher than that of patients without lymph node metastases (78.13 vs 25.00%, P < 0.05). The curative effective rate of patients with negative expression of VEGF was higher than that of patients with positive expression of VEGF (74.67 vs 41.40%, P < 0.05). 2. The expression of EGFR protein in male patients was higher than that of female patients (69.77 vs 35.29%, P < 0.05). Before treatment, the serum EGFR level in patients was higher than the normal group (P < 0.05). 3. The serum ES level in patients before and after treatment was significantly higher than in the normal group (P < 0.05). 4. The HER-2 positive rate in higher differentiated tumor tissue was lower than that in lower differentiated tumor tissue. (The positive rate of I, II, III grade was 70.00, 30.00, and 20.00%, respectively, P < 0.05). 5. The NF-κB positive rate in patients with lymph node metastases was higher than that of patients without lymph node metastases (65.63 vs 39.27%, P < 0.05), meanwhile median survival in the latter group was higher than that of the former group (P < 0.05). Our data suggest that the expression of VEGF and ES were different in Uygur, Han, and Kazakh patients in Xinjiang. The combined detection of tumor markers in serum and tissue is of direct significance for tumor therapy.
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Zhou YT, Xue YB, Chen D, Wang YJ, Zhang B, Ma XL. Atomic-scale configurations of synchroshear-induced deformation twins in the ionic MnS crystal. Sci Rep 2014; 4:5118. [PMID: 24874022 PMCID: PMC4038820 DOI: 10.1038/srep05118] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 05/07/2014] [Indexed: 11/10/2022] Open
Abstract
Deformation twinning was thought as impossible in ionic compounds with rock-salt structure due to the charge effect on {111} planes. Here we report the presence and formation mechanism of deformation {111} twins in the rock-salt manganese sulphide (MnS) inclusions embedded in a hot-rolled stainless steel. Based on the atomic-scale mapping under aberration-corrected scanning transmission electron microscopy, a dislocation-based mechanism involved two synchronized shear on adjacent atomic layers is proposed to describe the dislocation glide and consequently twinning formation. First-principles calculations of the energy barriers for twinning formation in MnS and comparing with that of PbS and MgO indicate the distinct dislocation glide scheme and deformation behaviors for the rock-salt compounds with different ionicities. This study may improve our understanding of the deformation mechanisms of rock-salt crystals and other ionic compounds.
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Yu Q, Zhou N, Nan Y, Zhang L, Li Y, Hao X, Xiong L, Lau WB, Ma XL, Wang H, Gao F. Effective glycaemic control critically determines insulin cardioprotection against ischaemia/reperfusion injury in anaesthetized dogs. Cardiovasc Res 2014; 103:238-47. [PMID: 24845581 DOI: 10.1093/cvr/cvu132] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
AIMS Experimental evidence has shown significant cardioprotective effects of insulin, whereas clinical trials produced mixed results without valid explanations. This study was designed to examine the effect of hyperglycaemia on insulin cardioprotective action in a preclinical large animal model of myocardial ischaemia/reperfusion (MI/R). METHODS AND RESULTS Anaesthetized dogs were subjected to MI/R (30 min/4 h) and randomized to normal plasma insulin/euglycaemia (NI/NG), normal-insulin/hyperglycaemia (NI/HG), high-insulin/euglycaemia (HI/NG), and high-insulin/hyperglycaemia (HI/HG) achieved by controlled glucose/insulin infusion. Endogenous insulin production was abolished by peripancreatic vessel ligation. Compared with the control animals (NI/NG), hyperglycaemia (NI/HG) significantly aggravated MI/R injury. Insulin elevation at clamped euglycaemia (HI/NG) protected against MI/R injury as evidenced by reduced infarct size, decreased necrosis and apoptosis, and alleviated inflammatory and oxidative stress (leucocyte infiltration, myeloperoxidase, and malondialdehyde levels). However, these cardioprotective effects of insulin were markedly blunted in hyperglycaemic animals (HI/HG). In vitro mechanistic study in neonatal rat cardiomyocytes revealed that insulin-stimulated tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and Akt was significantly attenuated by high glucose, accompanied by markedly increased IRS-1 O-GlcNAc glycosylation following hypoxia/reoxygenation. Inhibition of hexosamine biosynthesis with 6-diazo-5-oxonorleucine abrogated high glucose-induced O-GlcNAc modification and inactivation of IRS-1/Akt as well as cell injury. CONCLUSIONS Our results, derived from a canine model of MI/R, demonstrate that hyperglycaemia blunts insulin protection against MI/R injury via hyperglycaemia-induced glycosylation and subsequent inactivation of insulin-signalling proteins. Our findings suggest that prevention of hyperglycaemia is critical for achieving maximal insulin cardioprotection for the ischaemic/reperfused hearts.
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Zuo L, Bao H, Tian J, Wang X, Zhang S, He Z, Yan L, Zhao R, Ma XL, Liu H. Corrigendum to “Long-term active immunization with a synthetic peptide corresponding to the second extracellular loop of β1-adrenoceptor induces both morphological and functional cardiomyopathic changes in rats” [Int J Cardiol 149 (1) (2011) 89–94]. Int J Cardiol 2014. [DOI: 10.1016/j.ijcard.2014.01.106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Zhou YT, Zhang B, Zheng SJ, Wang J, San XY, Ma XL. Atomic-scale decoration for improving the pitting corrosion resistance of austenitic stainless steels. Sci Rep 2014; 4:3604. [PMID: 24398863 PMCID: PMC3884226 DOI: 10.1038/srep03604] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 12/03/2013] [Indexed: 11/09/2022] Open
Abstract
Stainless steels are susceptible to the localized pitting corrosion that leads to a huge loss to our society. Studies in the past decades confirmed that the pitting events generally originate from the local dissolution in MnS inclusions which are more or less ubiquitous in stainless steels. Although a recent study indicated that endogenous MnCr2O4 nano-octahedra within the MnS medium give rise to local nano-galvanic cells which are responsible for the preferential dissolution of MnS, effective solutions of restraining the cells from viewpoint of electrochemistry are being tantalizingly searched. Here we report such a galvanic corrosion can be greatly resisted via bathing the steels in Cu2+-containing solutions. This chemical bath generates Cu2−δS layers on the surfaces of MnS inclusions, invalidating the nano-galvanic cells. Our study provides a low-cost approach via an atomic scale decoration to improve the pitting corrosion resistance of stainless steels in a volume-treated manner.
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Xing D, Ma XL, Ma JX, Wang J, Yang Y, Chen Y. Association between use of benzodiazepines and risk of fractures: a meta-analysis. Osteoporos Int 2014; 25:105-20. [PMID: 24013517 DOI: 10.1007/s00198-013-2446-y] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 06/14/2013] [Indexed: 01/11/2023]
Abstract
UNLABELLED Benzodiazepines (BZDs) are some of the most commonly prescribed drugs in the world. It has been shown that BZD use could be associated with increased fracture risk. However, studies on the use of BZDs and fracture risk have yielded inconsistent results. Results from the present meta-analysis show that BZD use is associated with a moderate and clinically significant increase in the risk of fractures. INTRODUCTION The relationship between the use of BZDs and fracture risk has been neither well identified nor summarized. This meta-analysis reports on the use of BZDs, especially short-acting BZDs, and their correlation with a moderate and clinically significant increase in fracture risk. This analysis will provide evidence for clinicians to consider fracture risk when prescribing BZDs among the elderly population. This study was conducted to determine whether people who take BZDs are at an increased fracture risk. METHODS A systematic search of studies published through January 2013 was conducted using MEDLINE, EMBASE, OVID, and ScienceDirect. Case-control and cohort studies that assessed the relationship between BZD use and the risk of fractures were identified. Literature searches, study selections, methodological assessments, and data mining were independently conducted by two reviewers. Disagreements were resolved by consensus. STATA 12.0 software was used for the meta-analysis. Random effects models were used for pooled analysis due to heterogeneity among the studies. RESULTS There were 25 studies, including 19 case-control studies and 6 cohort studies, that met the inclusion criteria. Overall, the results of the meta-analysis indicated that BZD use was associated with a significantly increased fracture risk (relative risk (RR) = 1.25; 95% confidence intervals (CI), 1.17-1.34; p < 0.001). Increased fracture risk associated with BZD use was observed in participants aged ≥65 years old (RR = 1.26; 95% CI, 1.15-1.38; p < 0.001). When only hip fractures were included as the outcome measure, the RR increased to 1.35. However, subgroup meta-analyses showed that there was no significant association between BZD use and fracture risk in Eastern countries (RR = 1.27; 95% CI, 0.76-2.14; p = 0.362) as well as between long-acting BZD use and risk of fractures (RR = 1.21; 95% CI, 0.95-1.54; p = 0.12). After accounting for publication bias, we observed that the overall association between BZD use and fracture risk to be slightly weaker (RR = 1.21; 95% CI, 1.13-1.30) but still significant. CONCLUSION The results of this meta-analysis demonstrate that the use of BZD, especially short-acting BZD, is associated with a moderate and clinically significant increase in fracture risk. However, large prospective studies that minimize selection bias are necessary to determine a more accurate fracture risk associated with BZD use.
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Gong HT, Ma XL, Chen BX, Xu XY, Li Q, Guo CX, Du FH. Polymorphisms of the angiotensin II type 1 receptor gene affect antihypertensive response to angiotensin receptor blockers in hypertensive Chinese. GENETICS AND MOLECULAR RESEARCH 2013; 12:2068-75. [PMID: 23913386 DOI: 10.4238/2013.june.21.2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The renin-angiotensin-aldosterone system plays a key role in regulating blood pressure by maintaining vascular tone and the water/sodium balance. Many antihypertensive drugs target the renin-angiotensin-aldosterone system, but the effect differs considerably among hypertensive patients. We investigated whether genetic variants of the angiotensin II type 1 receptor are associated with blood pressure response to angiotensin II receptor blockers in hypertensive Chinese patients. After a 2-week single-blind placebo run-in period, 148 patients with mild-to-moderate primary hypertension received monotherapy with 80 mg/day telmisartan and then were followed up for 8 weeks. The 1166A/C, 573T/C, -810A/T, and -521C/T polymorphisms of the AT1R gene were determined through PCR and RFLP analysis. The relationship between these polymorphisms and changes in blood pressure was observed and evaluated after 8 weeks of treatment. Patients with the AT1R -521CC genotype had a significant reduction in diastolic blood pressure compared to those carrying the T allele. No significant reduction in blood pressure was found in individuals with the 1166A/C, 573T/C, or -810A/T polymorphisms of the AT1R gene. We conclude that only the AT1R -521CC genotype is associated with a significant decrease in blood pressure in response to telmisartan treatment in Chinese hypertensive patients.
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Ma XL, Zheng LW, Mao LT, Zhou LB, Wang AL. Neuropeptide Y in black seabream Acanthopagrus schlegelii: identification, distribution and mRNA expression responses to ghrelin. JOURNAL OF FISH BIOLOGY 2013; 82:1441-1447. [PMID: 23557320 DOI: 10.1111/jfb.12084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 01/25/2013] [Indexed: 06/02/2023]
Abstract
The coding region of neuropeptide Y (NPY) complementary (c)DNA was cloned from the hypothalamus RNA of black seabream Acanthopagrus schlegelii, including 297 bp coding for prepro-NPY of 98 amino acids. Real-time reverse transcriptase-polymerase chain reaction was performed to determine A. schlegelii npy gene expression; NPY messenger RNA (mRNA) was expressed highly in the brain and stomach. Treatment with acylated ghrelin significantly up-regulated NPY mRNA level in the hypothalamus, suggesting that NPY may be involved in regulating food intake of A. schlegelii.
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Lau WB, Zhang Y, Zhao J, Liu B, Wang X, Yuan Y, Christopher TA, Lopez B, Gao E, Koch WJ, Ma XL, Wang Y. Lymphotoxin-α is a novel adiponectin expression suppressor following myocardial ischemia/reperfusion. Am J Physiol Endocrinol Metab 2013; 304:E661-7. [PMID: 23360826 PMCID: PMC3602691 DOI: 10.1152/ajpendo.00012.2013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Recent clinical observations demonstrate adiponectin (APN), an adipocytokine with potent cardioprotective actions, is significantly reduced following myocardial ischemia/reperfusion (MI/R). However, mechanisms responsible for MI/R-induced hypoadiponectinemia remain incompletely understood. Adult male mice were subjected to 30-min MI followed by varying reperfusion periods. Adipocyte APN mRNA and protein expression and plasma APN and TNFα concentrations were determined. APN expression/production began to decline 3 h after reperfusion (reaching nadir 12 h after reperfusion), returning to control levels 7 days after reperfusion. Plasma TNFα levels began to increase 1 h after reperfusion, peaking at 3 h and returning to control levels 24 h after reperfusion. TNFα knockout significantly increased plasma APN levels 12 h after reperfusion but failed to improve APN expression/production 72 h after reperfusion. In contrast, TNF receptor-1 (TNFR1) knockout significantly restored APN expression 12 and 72 h after reperfusion, suggesting that other TNFR1 binding cytokines contribute to MI/R-induced APN suppression. Among many cytokines increased after MI/R, lymphotoxin-α (LTα) was the only cytokine remaining elevated 24-72 h after reperfusion. LTα knockout did not augment APN levels 12 h post-reperfusion, but did so by 72 h. Finally, in vitro treatment of adipocytes with TNFα and LTα at concentrations seen in MI/R plasma additively inhibited APN expression/production in TNFR1-dependent fashion. Our study demonstrates for the first time that LTα is a novel suppressor of APN expression and contributes to the sustained hypoadiponectinemia following MI/R. Combining anti-TNFα with anti-LTα strategies may achieve the best effects restoring APN in MI/R patients.
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MESH Headings
- 3T3-L1 Cells
- Adiponectin/blood
- Adiponectin/deficiency
- Adiponectin/genetics
- Adiponectin/metabolism
- Adipose Tissue, White/immunology
- Adipose Tissue, White/metabolism
- Animals
- Down-Regulation
- Lymphotoxin-alpha/blood
- Lymphotoxin-alpha/genetics
- Lymphotoxin-alpha/metabolism
- Male
- Metabolism, Inborn Errors/etiology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myocardial Ischemia/blood
- Myocardial Ischemia/immunology
- Myocardial Ischemia/metabolism
- Myocardial Reperfusion Injury/blood
- Myocardial Reperfusion Injury/immunology
- Myocardial Reperfusion Injury/metabolism
- Myocardial Reperfusion Injury/physiopathology
- RNA Interference
- RNA, Messenger/metabolism
- RNA, Small Interfering
- Receptors, Tumor Necrosis Factor, Type I/antagonists & inhibitors
- Receptors, Tumor Necrosis Factor, Type I/genetics
- Receptors, Tumor Necrosis Factor, Type I/metabolism
- Time Factors
- Tumor Necrosis Factor-alpha/blood
- Tumor Necrosis Factor-alpha/genetics
- Tumor Necrosis Factor-alpha/metabolism
- Up-Regulation
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Zhou X, Dai YY, Ma XL. Be alert to the alterations in the biological characteristics in heterogeneous vancomycin-intermediate Staphylococcus aureus. Indian J Med Microbiol 2012; 30:215-7. [DOI: 10.4103/0255-0857.96696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Zhu WW, Ma XL, Guo AL, Zhao HY, Luo HH. Neuroprotective effects of NEP1-40 and fasudil on Nogo-A expression in neonatal rats with hypoxic-ischemic brain damage. GENETICS AND MOLECULAR RESEARCH 2011; 10:2987-95. [PMID: 22180032 DOI: 10.4238/2011.november.29.9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The hypoxic-ischemic encephalopathy caused by peripartum asphyxia is a serious disease in newborn infants, and effective therapies need to be developed to reduce injury-related disorders. We evaluated the effects of NEP1-40 and fasudil on Nogo-A expression in neonatal hypoxic-ischemic brain damage (HIBD) rats. Seven-day-old Wistar rats were randomly divided into control, HIBD, NEP1-40, and fasudil groups. NEP1-40 and fasudil groups were injected intraperitoneally with these compounds. Rat brains at 6, 24, 72 h, and 7 days after HIBD were collected to determine histopathological damage and the expression levels of Nogo-A. Histopathological damage was reduced in NEP1-40 and fasudil groups compared with the untreated HIBD group. The expression of Nogo-A in the HIBD group was significantly higher than that in control, NEP1-40 and fasudil groups at the same times. Compared with the fasudil group, the expression levels of Nogo-A were significantly reduced in the NEP1-40 group. We conclude that NPE1-40 and fasudil have potential for neuroprotective effects in the neonatal rat HIBD model, mediated by inhibiting Nogo-A/ Rho pathways.
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Lau WB, Tao L, Wang Y, Li R, Ma XL. Systemic adiponectin malfunction as a risk factor for cardiovascular disease. Antioxid Redox Signal 2011; 15:1863-73. [PMID: 21091079 PMCID: PMC3159112 DOI: 10.1089/ars.2010.3743] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Adiponectin (Ad) is an abundant protein hormone regulatory of numerous metabolic processes. The 30 kDa protein originates from adipose tissue, with full-length and globular domain circulatory forms. A collagenous domain within Ad leads to spontaneous self-assemblage into various oligomeric isoforms, including trimers, hexamers, and high-molecular-weight multimers. Two membrane-spanning receptors for Ad have been identified, with differing concentration distribution in various body tissues. The major intracellular pathway activated by Ad includes phosphorylation of AMP-activated protein kinase, which is responsible for many of Ad's metabolic regulatory, anti-inflammatory, vascular protective, and anti-ischemic properties. Additionally, several AMP-activated protein kinase-independent mechanisms responsible for Ad's anti-inflammatory and anti-ischemic (resulting in cardioprotective) effects have also been discovered. Since its 1995 discovery, Ad has garnered considerable attention for its role in diabetic and cardiovascular pathology. Clinical observations have demonstrated the association of hypoadiponectinemia in patients with obesity, cardiovascular disease, and insulin resistance. In this review, we elaborate currently known information about Ad malfunction and deficiency pertaining to cardiovascular disease risk (including atherosclerosis, endothelial dysfunction, and cardiac injury), as well as review evidence supporting Ad resistance as a novel risk factor for cardiovascular injury, providing insight about the future of Ad research and the protein's potential therapeutic benefits.
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Aihara KI, Mogi M, Shibata R, Bishop-Bailey D, Ma XL. Interactions between CKD and MetS and the Development of CVD. Cardiol Res Pract 2011; 2011:878065. [PMID: 21629800 PMCID: PMC3099205 DOI: 10.4061/2011/878065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 03/17/2011] [Indexed: 11/20/2022] Open
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Cilenti L, Balakrishnan MP, Wang XL, Ambivero C, Sterlicchi M, del Monte F, Ma XL, Zervos AS. Regulation of Abro1/KIAA0157 during myocardial infarction and cell death reveals a novel cardioprotective mechanism for Lys63-specific deubiquitination. J Mol Cell Cardiol 2010; 50:652-61. [PMID: 21195082 DOI: 10.1016/j.yjmcc.2010.12.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 12/15/2010] [Accepted: 12/18/2010] [Indexed: 01/31/2023]
Abstract
Abro1 (also known as KIAA0157) is a scaffold protein that recruits polypeptides to assemble the BRISC (BRCC36-containing isopeptidase complex) deubiquitinating (DUB) enzyme. The four subunits of BRISC enzyme include Abro1, NBA1, BRE, and BRCC36 proteins. The DUB activity of the BRISC enzyme is exclusively directed against Lys63-linked polyubiquitin that does not have a proteolytic role but regulates protein function. In this report, we identified Abro1 as a specific interactor of THAP5, a zinc finger transcription factor that is involved in G2/M control and apoptosis. Abro1 was predominantly expressed in the heart and its protein level was regulated following experimentally induced myocardial ischemia/reperfusion (MI/R) injury. Furthermore, in patients with coronary artery disease (CAD), there was a dramatic increase in Abro1 protein level in the myocardial infarction (MI) area. Increase in Abro1 leads to a significant reduction in Lys63-linked ubiquitination of specific protein targets. Reducing the Abro1 protein level exacerbated cellular damage and cell death of cardiomyocytes due to MI/R injury. Additionally, overexpression of Abro1 in a heterologous system provided significant protection against oxidative stress-induced apoptosis. In conclusion, our results demonstrate that Abro1 protein level substantially increases in myocardial injury and coronary artery disease and this up-regulation is part of a novel cardioprotective mechanism. In addition, our data suggest a potential new link between Lys63-specific ubiquitination, its modulation by the BRISC DUB enzyme, and the development and progression of heart disease.
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Wang X, Ma XL, Feng X, Zheng YF. Controlled synthesis and characterization of ZnSe quantum dots. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:7812-7815. [PMID: 21138039 DOI: 10.1166/jnn.2010.2905] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Adopting improved metal-organic "Green method," Colloidal ZnSe quantum dots were synthesized by using cheap and low toxic zinc oxide (ZnO) in an organic solvent system of 1-hexadecylamine (HDA), lauric acid (LA) and tri-n-octylphosphine (TOP). The effects of HDA dosage, injection temperature, growth temperature and time on the microstructure and optical properties of ZnSe were studied by means of X-Ray diffraction(XRD), transmission electron microscopy (TEM), spectrofluorometers and ultraviolet spectrophotometer, respectively. The results showed that ZnSe quantum dots with the best range of the size evolution were obtained under the condition of injection at 280 degrees C and growth at 240 degrees C by choosing the optimal parameters of ZnO:HDA:LA= 1:2.1:5.2 and TOPSe = 1 mol/L. Its size became larger and the emission peak shifted obviously to red with increasing the growth time. Meanwhile, the obtained ZnSe was of the wurtzite structure, had good uniformity and fluorescent characteristics.
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Gao E, Lei YH, Shang X, Huang ZM, Zuo L, Boucher M, Fan Q, Chuprun JK, Ma XL, Koch WJ. A novel and efficient model of coronary artery ligation and myocardial infarction in the mouse. Circ Res 2010; 107:1445-53. [PMID: 20966393 DOI: 10.1161/circresaha.110.223925] [Citation(s) in RCA: 482] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
RATIONALE coronary artery ligation to induce myocardial infarction (MI) in mice is typically performed by an invasive and time-consuming approach that requires ventilation and chest opening (classic method), often resulting in extensive tissue damage and high mortality. We developed a novel and rapid surgical method to induce MI that does not require ventilation. OBJECTIVE the purpose of this study was to develop and comprehensively describe this method and directly compare it to the classic method. METHODS AND RESULTS male C57/B6 mice were grouped into 4 groups: new method MI (MI-N) or sham (S-N) and classic method MI (MI-C) or sham (S-C). In the new method, heart was manually exposed without intubation through a small incision and MI was induced. In the classic method, MI was induced through a ventilated thoracotomy. Similar groups were used in an ischemia/reperfusion injury model. This novel MI procedure is rapid, with an average procedure time of 1.22 ± 0.05 minutes, whereas the classic method requires 23.2 ± 0.6 minutes per procedure. Surgical mortality was 3% in MI-N and 15.9% in MI-C. The rate of arrhythmia was significantly lower in MI-N. The postsurgical levels of tumor necrosis factor-α and myeloperoxidase were lower in new method, indicating less inflammation. Overall, 28-day post-MI survival rate was 68% with MI-N and 48% with MI-C. Importantly, there was no difference in infarct size or post-MI cardiac function between the methods. CONCLUSIONS this new rapid method of MI in mice represents a more efficient and less damaging model of myocardial ischemic injury compared with the classic method.
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Chen G, Lai W, Liu F, Mao Q, Tu F, Wen J, Xiao H, Zhang JC, Zhu T, Chen B, Hu ZY, Li RM, Liang Z, Nie H, Yan H, Yang BX, Du Q, Huang WX, Jiang YW, Kwan ASK, Song L, Wu CM, Xiang T, Xu HW, Lau WB, Song HB, Wen CB, Yao ZH, Zhang L, Zeng J, Dai YE, Lopez BL, Zheng JQ, Zhou J, Christopher TA, Ma XL, Yu H, Xu LL, Guo Q, Song ZP, Volinn E, Kryger K, Cao Y, Ge H, Liu H, Luo CZ, Tao W, Zuo YX, Liu J. The dragon strikes: lessons from the Wenchuan earthquake. Anesth Analg 2010; 110:908-15. [PMID: 20185667 DOI: 10.1213/ane.0b013e3181cbc62c] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Tao L, Wang Y, Gao E, Zhang H, Yuan Y, Lau WB, Chan L, Koch WJ, Ma XL. Adiponectin: an indispensable molecule in rosiglitazone cardioprotection following myocardial infarction. Circ Res 2009; 106:409-17. [PMID: 19940263 DOI: 10.1161/circresaha.109.211797] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RATIONALE Patients treated with peroxisome proliferator-activated receptor (PPAR)-gamma agonist manifest favorable metabolic profiles associated with increased plasma adiponectin (APN). However, whether increased APN production as a result of PPAR-gamma agonist treatment is an epiphenomenon or is causatively related to the cardioprotective actions of PPAR-gamma remains unknown. OBJECTIVE To determine the role of APN in rosiglitazone (RSG) cardioprotection against ischemic heart injury. METHODS AND RESULTS Adult male wild-type (WT) and APN knockdown/knockout (APN(+ or -) and APN(- or -)) mice were treated with vehicle or RSG (20 mg/kg per day), and subjected to coronary artery ligation 3 days after beginning treatment. In WT mice, RSG (7 days) significantly increased adipocyte APN expression, elevated plasma APN levels (2.6-fold), reduced infarct size (17% reduction), decreased apoptosis (0.23 + or - 0.02% versus 0.47 + or - 0.04% TUNEL-positive in remote nonischemic area), attenuated oxidative stress (48.5% reduction), and improved cardiac function (P<0.01). RSG-induced APN production and cardioprotection were significantly blunted (P<0.05 versus WT) in APN(+ or -), and completely lost in APN(- or -) (P>0.05 versus vehicle-treated APN(- or -) mice). Moreover, treatment with RSG for up to 14 days significantly improved the postischemic survival rate of WT mice (P<0.05 versus vehicle group) but not APN knockdown/knockout mice. CONCLUSIONS The cardioprotective effects of PPAR-gamma agonists are critically dependent on its APN stimulatory action, suggesting that under pathological conditions where APN expression is impaired (such as advanced type 2 diabetes), the harmful cardiovascular effects of PPAR-gamma agonists may outweigh its cardioprotective benefits.
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Yan L, Xu Y, Yao H, Xue W, Tian J, Ren H, Wu Y, Yang G, Ma XL, Liu H. The effects of autoantibodies against the second extracellular loop of alpha(1)-adrenoceptor on vasoconstriction. Basic Res Cardiol 2009; 104:581-9. [PMID: 19330480 DOI: 10.1007/s00395-009-0020-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 03/05/2009] [Accepted: 03/09/2009] [Indexed: 10/21/2022]
Abstract
Recent studies have demonstrated the presence of autoantibodies against alpha(1)-adrenoceptor (alpha(1)-AAB) in the serum of patients with primary hypertension, and that these autoantibodies exert adrenergic-agonist-like effects. However, their role in the development of hypertension remains unclear. The current study determined whether alpha(1)-AAB can cause vascular contraction, and further investigated the cellular receptors that mediate their vasoactivity. Enzyme-linked immunosorbent assay (ELISA) was used to detect alpha(1)-AAB in blood samples collected from 73 patients with primary hypertension and 86 normotensive patients. IgGs were purified from mixed sera from 25 alpha(1)-AAB-positive hypertensive patients and 20 alpha(1)-AAB-negative normotensives, respectively. The vasoconstrictive effect of purified IgG from the sera of either hypertensive or normotensive patients was observed in isolated rat thoracic aorta, coronary artery, renal artery, middle cerebral artery, and mesenteric artery. The effects of alpha(1)-AAB administration on mean arterial blood pressure in vivo were also assessed. The frequency of alpha(1)-AAB presence was considerably higher in patients with primary hypertension than normotensive subjects (34.2 vs. 10.5%, P < 0.01). In isolated thoracic aortic rings, renal artery, middle cerebral artery, and coronary artery segments, alpha(1)-AAB induced vasoconstriction in a concentration-dependent fashion, which can be completely blocked by prazosin, a selective alpha(1)-adrenoceptor antagonist. The mean arterial pressure significantly increased after the administration of alpha(1)-AAB in vivo. Our results demonstrated that the alpha(1)-AAB (which exhibited remarkable effects of vascular contraction in vitro, elevated blood pressure in vivo, and showed no desensitization phenomena) may play a role in both elevating vascular resistance and the development and maintenance of hypertension.
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Goldstein BJ, Scalia RG, Ma XL. Protective vascular and myocardial effects of adiponectin. ACTA ACUST UNITED AC 2008; 6:27-35. [PMID: 19029992 DOI: 10.1038/ncpcardio1398] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 09/30/2008] [Indexed: 02/07/2023]
Abstract
Adiponectin is an abundant plasma protein secreted from adipocytes that elicits protective effects in the vasculature and myocardium. In obesity and insulin-resistant states, adiponectin levels are reduced and loss of its protective effects might contribute to the excess cardiovascular risk observed in these conditions. Adiponectin ameliorates the progression of macrovascular disease in rodent models, consistent with its correlation with improved vascular outcomes in epidemiological studies. The mechanisms of adiponectin signaling are multiple and vary among its cellular sites of action. In endothelial cells, adiponectin enhances production of nitric oxide, suppresses production of reactive oxygen species, and protects cells from inflammation that results from exposure to high glucose levels or tumor necrosis factor, through activation of AMP-activated protein kinase and cyclic AMP-dependent protein kinase (also known as protein kinase A) signaling cascades. In the myocardium, adiponectin-mediated protection from ischemia-reperfusion injury is linked to cyclo-oxygenase-2-mediated suppression of tumor necrosis factor signaling, inhibition of apoptosis by AMP-activated protein kinase, and inhibition of excess peroxynitrite-induced oxidative and nitrative stress. In this Review, we provide an update of studies of the signaling effects of adiponectin in endothelial cells and cardiomyocytes.
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Xu XM, Hua JL, Gao ZM, Lei AM, Ma XL, Yang CR, Huang JYSW, Fan JZ, Dou ZY. Fetal porcine mesenchymal stem cells nuclear transfer and isolation of embryonic stem cells-like derived from cloned blastocysts. Cell Res 2008. [DOI: 10.1038/cr.2008.233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Li S, Tao L, Jiao X, Liu H, Cao Y, Lopez B, Luan RH, Christopher T, Ma XL. TNFalpha-initiated oxidative/nitrative stress mediates cardiomyocyte apoptosis in traumatic animals. Apoptosis 2008; 12:1795-802. [PMID: 17701456 DOI: 10.1007/s10495-007-0108-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Whole body non-penetrating trauma causes myocardial infarction in humans and mechanical trauma (MT) results in cardiac dysfunction in animals. Our recent study demonstrated that incubation of cardiomyocytes with plasma isolated from MT animals causes significant cardiomyocyte apoptosis that can be blocked by neutralization of TNFalpha. The present study attempted to obtain direct in vivo evidence to support that overproduction of TNFalpha plays a causative role in trauma-induced cardiomyocyte apoptosis. Non-lethal MT caused significant TNFalpha overproduction (2.4-fold at 1.5 h after MT) and increased cardiomyocyte apoptosis (starting 3 h and peaking 12 h after MT). Pharmacological inhibition of TNFalpha with etanercept or TNFalpha gene deletion reduced post-trauma myocyte apoptosis (P<0.01). Expression of iNOS and NADPH oxidase, overproduction of NO and O2-, and excessive protein nitration in the MT heart were all significantly reduced in etanercept-treated or TNFalpha-/- mice, suggesting that oxidative/nitrative stress may contribute to TNFalpha-initiated myocyte apoptosis in MT hearts. Additional experiments demonstrated that inhibiting iNOS (1400W) or NADPH oxidase (apocynin), or scavenging peroxynitrite (FP15) significantly reduced myocyte apoptosis in MT animals (P<0.01). Collectively, these data demonstrated that non-lethal mechanical trauma caused significant TNFalpha production that in turn stimulated myocardial apoptosis via oxidative/nitrative stress.
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Huang CQ, Ma GZ, Tao MD, Ma XL, Feng J, Liu QX. The Relationship between Renal Injury and Change in Vitamin D Metabolism in Aged Rats with Insulin Resistance or Type 2 Diabetes Mellitus. J Int Med Res 2008; 36:289-95. [PMID: 18380939 DOI: 10.1177/147323000803600211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Insulin resistance (IR), IR treated with vitamin D, IR treated with 1α-hydroxyvitamin D (1α-(OH)D), type 2 diabetes mellitus (T2DM), T2DM treated with vitamin D and T2DM treated with 1a-(OH)D were studied in animal models using aged Wistar rats. Glucose infusion rates and levels of urinary albumin (UA), serum 25-hydroxyvitamin D (25-(OH)D) and 1, 25-dihydroxyvitamin D (1, 25-(OH)2D) were measured. T2DM rats had higher UA than IR or normal rats, and levels of 25-(OH)D in all models were similar. IR rats had higher 1, 25-(OH)2D levels than T2DM rats, and had lower 1, 25-(OH)2D levels than normal rats. Treating IR or T2DM rats with vitamin D had no effect on 25-(OH)D or 1, 25-(OH)2D. Administration of 1α-(OH)D significantly increased 1, 25-(OH)2D in IR rats to above-normal levels, and significantly increased 1, 25-(OH)2D in T2DM rats to normal levels. In IR or T2DM, abnormal vitamin D metabolism is characterized by 1, 25-(OH)2D deficiency and is related to renal injury.
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Li R, Wang WQ, Zhang H, Yang X, Fan Q, Christopher TA, Lopez BL, Tao L, Goldstein BJ, Gao F, Ma XL. Adiponectin improves endothelial function in hyperlipidemic rats by reducing oxidative/nitrative stress and differential regulation of eNOS/iNOS activity. Am J Physiol Endocrinol Metab 2007; 293:E1703-8. [PMID: 17895290 DOI: 10.1152/ajpendo.00462.2007] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Plasma adiponectin level is significantly reduced in patients with metabolic syndrome, and vascular dysfunction is an important pathological event in these patients. However, whether adiponectin may protect endothelial cells and attenuate endothelial dysfunction caused by metabolic disorders remains largely unknown. Adult rats were fed with a regular or a high-fat diet for 14 wk. The aorta was isolated, and vascular segments were incubated with vehicle or the globular domain of adiponectin (gAd; 2 mug/ml) for 4 h. The effect of gAd on endothelial function, nitric oxide (NO) and superoxide production, nitrotyrosine formation, gp91(phox) expression, and endothelial nitric oxide synthase (eNOS)/inducible NOS (iNOS) activity/expression was determined. Severe endothelial dysfunction (maximal vasorelaxation in response to ACh: 70.3 +/- 3.3 vs. 95.2 +/- 2.5% in control, P < 0.01) was observed in hyperlipidemic aortic segments, and treatment with gAd significantly improved endothelial function (P < 0.01). Paradoxically, total NO production was significantly increased in hyperlipidemic vessels, and treatment with gAd slightly reduced, rather than increased, total NO production in these vessels. Treatment with gAd reduced (-78%, P < 0.01) superoxide production and peroxynitrite formation in hyperlipidemic vascular segments. Moreover, a moderate attenuation (-30%, P < 0.05) in gp91(phox) and iNOS overexpression in hyperlipidemic vessels was observed after gAd incubation. Treatment with gAd had no effect on eNOS expression but significantly increased eNOS phosphorylation (P < 0.01). Most noticeably, treatment with gAd significantly enhanced eNOS (+83%) but reduced iNOS (-70%, P < 0.01) activity in hyperlipidemic vessels. Collectively, these results demonstrated that adiponectin protects the endothelium against hyperlipidemic injury by multiple mechanisms, including promoting eNOS activity, inhibiting iNOS activity, preserving bioactive NO, and attenuating oxidative/nitrative stress.
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Li S, Jiao X, Tao L, Liu H, Cao Y, Lopez BL, Christopher TA, Ma XL. Tumor necrosis factor-α in mechanic trauma plasma mediates cardiomyocyte apoptosis. Am J Physiol Heart Circ Physiol 2007; 293:H1847-52. [PMID: 17616742 DOI: 10.1152/ajpheart.00578.2007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mechanical traumatic injury causes cardiomyocyte apoptosis and cardiac dysfunction. However, the signaling mechanisms leading to posttraumatic cardiomyocyte apoptosis remains unclear. The present study attempted to identify the molecular mechanisms responsible for cardiomyocyte apoptosis induced by trauma. Normal cardiomyocytes (NC) or traumatic cardiomyocytes (TC; isolated immediately after trauma) were cultured with normal plasma (NP) or traumatic plasma (TP; isolated 1.5 h after trauma) for 12 h, and apoptosis was determined by caspase-3 activation. Exposure of TC to NP failed to induce significant cardiomyocyte apoptosis. In contrast, exposure of NC to TP resulted in a greater than twofold increase in caspase-3 activation ( P < 0.01). Incubation of cardiomyocytes with cytomix (a mixture of TNF-α, IL-1β, and IFN-γ) or TNF-α alone, but not with IL-1β or IFN-γ alone, caused significant caspase-3 activation ( P < 0.01). TP-induced caspase-3 activation was virtually abolished by an anti-TNF-α antibody, and TP isolated from TNF-α−/− mice failed to induce caspase-3 activation. Moreover, incubation of cardiomyocytes with TP upregulated inducible nitric oxide (NO) synthase (iNOS)/NADPH oxidase expression, increased NO/superoxide production, and increased cardiomyocyte protein nitration (measured by nitrotyrosine content). These oxidative/nitrative stresses and the resultant cardiomyocyte caspase-3 activation can be blocked by neutralization of TNF-α (anti-TNF-α antibody), inhibition of iNOS (1400W), or NADPH oxidase (apocynin) and scavenging of peroxynitrite (FP15) ( P < 0.01). Taken together, our study demonstrated that there exists a TNF-α-initiated, cardiomyocyte iNOS/NADPH oxidase-dependent, peroxynitrite-mediated signaling pathway that contributes to posttraumatic myocardial apoptosis. Therapeutic interventions that block this signaling cascade may attenuate posttraumatic cardiac injury and reduce the incidence of secondary organ dysfunction after trauma.
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Goldstein BJ, Scalia R, Ma XL, Mahadev K, Wu X, Ouedraogo R. Comment on: Hattori et al. (2007) Globular adiponectin activates nuclear factor-kappaB and activating protein-1 and enhances angiotensin II-induced proliferation in cardiac fibroblasts: Diabetes 56:804-808. Diabetes 2007; 56:e7-8; author reply e9-10. [PMID: 17596407 DOI: 10.2337/db07-0328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Zhang H, Tao L, Jiao X, Gao E, Lopez BL, Christopher TA, Koch W, Ma XL. Nitrative thioredoxin inactivation as a cause of enhanced myocardial ischemia/reperfusion injury in the aging heart. Free Radic Biol Med 2007; 43:39-47. [PMID: 17561092 PMCID: PMC1949486 DOI: 10.1016/j.freeradbiomed.2007.03.016] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Revised: 02/20/2007] [Accepted: 03/07/2007] [Indexed: 10/23/2022]
Abstract
Several recent studies have demonstrated that thioredoxin (Trx) is an important antiapoptotic/cytoprotective molecule. The present study was designed to determine whether Trx activity is altered in the aging heart in a way that may contribute to increased susceptibility to myocardial ischemia/reperfusion (MI/R). Compared to young animals, MI/R-induced cardiomyocyte apoptosis and infarct size were increased in aging animals (p<0.01). Trx activity was decreased in the aging heart before MI/R, and this difference was further amplified after MI/R. Trx expression was moderately increased and Trx nitration, a posttranslational modification that inhibits Trx activity, was increased in the aging heart. Moreover, Trx-aptosis-regulating kinase-1 (Trx-ASK1) complex formation was reduced and activity of p38 mitogen-activated protein kinase (MAPK) was increased. Treatment with FP15 (a peroxynitrite decomposition catalyst) reduced Trx nitration, increased Trx activity, restored Trx-ASK1 interaction, reduced P38 MAPK activity, attenuated caspase 3 activation, and reduced infarct size in aging animals (p<0.01). Our results demonstrated that Trx activity is decreased in the aging heart by posttranslational nitrative modification. Interventions that restore Trx activity in the aging heart may be novel therapies to attenuate MI/R injury in aging patients.
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Tao L, Gao E, Jiao X, Yuan Y, Li S, Christopher TA, Lopez BL, Koch W, Chan L, Goldstein BJ, Ma XL. Adiponectin cardioprotection after myocardial ischemia/reperfusion involves the reduction of oxidative/nitrative stress. Circulation 2007; 115:1408-16. [PMID: 17339545 DOI: 10.1161/circulationaha.106.666941] [Citation(s) in RCA: 359] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Several clinical studies have demonstrated that levels of adiponectin are significantly reduced in patients with type 2 diabetes and that adiponectin levels are inversely related to the risk of myocardial ischemia. The present study was designed to determine the mechanism by which adiponectin exerts its protective effects against myocardial ischemia/reperfusion. METHODS AND RESULTS Adiponectin-/- or wild-type mice were subjected to 30 minutes of myocardial ischemia followed by 3 hours or 24 hours (infarct size and cardiac function) of reperfusion. Myocardial infarct size and apoptosis, production of peroxynitrite, nitric oxide (NO) and superoxide, and inducible NO synthase (iNOS) and gp91(phox) protein expression were compared. Myocardial apoptosis and infarct size were markedly enhanced in adiponectin-/- mice (P<0.01). Formation of NO, superoxide, and their cytotoxic reaction product, peroxynitrite, were all significantly higher in cardiac tissue obtained from adiponectin-/- than from wild-type mice (P<0.01). Moreover, myocardial ischemia/reperfusion-induced iNOS and gp91(phox) protein expression was further enhanced, but endothelial NOS phosphorylation was reduced in cardiac tissue from adiponectin-/- mice. Administration of the globular domain of adiponectin 10 minutes before reperfusion reduced myocardial ischemia/reperfusion-induced iNOS/gp91(phox) protein expression, decreased NO/superoxide production, blocked peroxynitrite formation, and reversed proapoptotic and infarct-enlargement effects observed in adiponectin-/- mice. CONCLUSIONS The present study demonstrates that adiponectin is a natural molecule that protects hearts from ischemia/reperfusion injury by inhibition of iNOS and nicotinamide adenine dinucleotide phosphate-oxidase protein expression and resultant oxidative/nitrative stress.
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Wang HC, Zhang HF, Guo WY, Su H, Zhang KR, Li QX, Yan W, Ma XL, Lopez BL, Christopher TA, Gao F. Hypoxic postconditioning enhances the survival and inhibits apoptosis of cardiomyocytes following reoxygenation: role of peroxynitrite formation. Apoptosis 2007; 11:1453-60. [PMID: 16761110 DOI: 10.1007/s10495-006-7786-z] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Our previous study has shown that slow or "controlled" reperfusion for the ischemic heart reduces cardiomyocyte injury and myocardial infarction, while the mechanisms involved are largely unclear. In this study, we tested the hypothesis that enhancement of survival and prevention of apoptosis in hypoxic/reoxygenated cardiomyocytes by hypoxic postconditioning (HPC) are associated with the reduction in peroxynitrite (ONOO(-)) formation induced by hypoxia/reoxygenation (H/R). METHODS Isolated adult rat cardiomyocytes were exposed to 2 h of hypoxia followed by 3 h of reoxygenation. After 2 h of hypoxia the cardiomyocytes were either abruptly reperfused with pre-oxygenized culture medium or postconditioned by two cycles of 5 min of brief reoxygenation and 5 min of re-hypoxia followed by 160 min of abrupt reoxygenation. RESULTS H/R resulted in severe injury in cardiomyocytes as evidenced by decreased cell viability, increased LDH leakage in the culture medium, increased apoptotic index (P values all less than 0.01 vs. normoxia control group) and DNA ladder formation, which could be significantly attenuated by HPC treatment applied before the abrupt reoxygenation (P < 0.05 vs. H/R group). In addition, H/R induced a significant increase in ONOO(-) formation as determined by nitrotyrosine content in cardiomyocytes (P < 0.01 vs. normoxia control). Treatment with the potent ONOO(-) scavenger uric acid (UA) at reoxygenation significantly decreased ONOO(-) production and protected myocytes against H/R injury, whereas the same treatment with UA could not further enhance myocyte survival in HPC group (P > 0.05 vs. HPC alone). Statistical analysis showed that cell viability closely correlated inversely with myocyte ONOO(-) formation (P < 0.01). CONCLUSION These data demonstrate that hypoxic postconditioning protects myocytes against apoptosis following reoxygenation and enhances myocytes survival, which is partly attributable to the reduced ONOO(-) formation following reoxygenation.
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Yuan Y, Jiao X, Tao L, Christopher T, Lopez B, Ma XL. Lipopolysaccharide Inhibits Thioredoxin Activity in Vitro and in Vivo. FASEB J 2007. [DOI: 10.1096/fasebj.21.6.a1279-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tao L, Jiao X, Yuan Y, Christopher T, Lopez B, Chan L, Goldstein B, Ma XL. Inhibition of Peroxynitrite Formation Attenuates MI/R Injury in Adiponectin Deficient Mice. FASEB J 2007. [DOI: 10.1096/fasebj.21.6.a1374-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Jiao X, Hu A, Tao L, Lopez B, Christopher T, Sun J, Ma XL. Chronic isoproterenol stimulation induces cardiomyocyte apoptosis through p38‐cytokine‐iNOS pathway. FASEB J 2007. [DOI: 10.1096/fasebj.21.6.a1375-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Tao L, Jiao X, Gao E, Lau WB, Yuan Y, Lopez B, Christopher T, RamachandraRao SP, Williams W, Southan G, Sharma K, Koch W, Ma XL. Nitrative inactivation of thioredoxin-1 and its role in postischemic myocardial apoptosis. Circulation 2006; 114:1395-402. [PMID: 16966583 DOI: 10.1161/circulationaha.106.625061] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Intracellular proteins involved in oxidative stress and apoptosis are nitrated in diseased tissues but not in normal tissues; definitive evidence to support a causative link between a specific protein that is nitratively modified with tissue injury in a specific disease is limited, however. The aims of the present study were to determine whether thioredoxin (Trx), a novel antioxidant and antiapoptotic molecule, is susceptible to nitrative inactivation and to establish a causative link between Trx nitration and postischemic myocardial apoptosis. METHODS AND RESULTS In vitro exposure of human Trx-1 to 3-morpholinosydnonimine resulted in significant Trx-1 nitration and almost abolished Trx-1 activity. 3-morpholinosydnonimine-induced nitrative Trx-1 inactivation was completely blocked by MnTE-2-PyP(5+) (a superoxide dismutase mimetic) and markedly attenuated by PTIO (a nitric oxide scavenger). Administration of either reduced or oxidized Trx-1 in vivo attenuated myocardial ischemia/reperfusion injury (>50% reduction in apoptosis and infarct size, P<0.01). However, administration of nitrated Trx-1 failed to exert a cardioprotective effect. In cardiac tissues obtained from ischemic/reperfused heart, significant Trx-1 nitration was detected, Trx activity was markedly inhibited, Trx-1/ASK1 (apoptosis signal-regulating kinase-1) complex formation was abolished, and apoptosis signal-regulating kinase-1 activity was increased. Treatment with either FP15 (a peroxynitrite decomposition catalyst) or MnTE-2-PyP(5+) 10 minutes before reperfusion blocked nitrative Trx inactivation, attenuated apoptosis signal-regulating kinase-1 activation, and reduced postischemic myocardial apoptosis. CONCLUSIONS These results strongly suggest that nitrative inactivation of Trx plays a proapoptotic role under those pathological conditions in which production of reactive nitrogen species is increased and that antinitrating treatment may have therapeutic value in those diseases, such as myocardial ischemia/reperfusion, in which pathological apoptosis is increased.
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Tao L, Gao E, Hu A, Coletti C, Wang Y, Christopher TA, Lopez BL, Koch W, Ma XL. Thioredoxin reduces post-ischemic myocardial apoptosis by reducing oxidative/nitrative stress. Br J Pharmacol 2006; 149:311-8. [PMID: 16921396 PMCID: PMC2014279 DOI: 10.1038/sj.bjp.0706853] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND PURPOSE Thioredoxin (Trx) is an oxidoreductase that prevents free radical-induced cell death in cultured cells. Here we assessed the mechanism(s) underlying the cardioprotective effects of Trx in vivo. EXPERIMENTAL APPROACH The effects of myocardial ischemia (30 min) and reperfusion were measured in mice, with assays of myocardial apoptosis, superoxide production, NOx and nitrotyrosine content, and myocardial infarct size. Recombinant human Trx (rhTrx, 0.7-20 mg kg(-1), i.p.) was given 10 min before reperfusion. KEY RESULTS Treatment with 2 mg kg(-1) rhTrx significantly decreased myocardial apoptosis and reduced infarct size (P<0.01). Nitrotyrosine content of cardiomyocytes was markedly reduced in rhTrx-treated animals (P<0.01). To further identify the mechanisms by which rhTrx may exert its anti-nitrative effect, iNOS expression and production of NOx and superoxide were determined. Treatment with rhTrx had no significant effect on iNOS expression or NOx content in the ischemic/reperfused heart. However, it markedly upregulated mSOD and reduced tissue superoxide content. To further establish a causative link between the anti- peroxynitrite effect and the cardioprotective effect of rhTrx, cultured adult cardiomyocytes were incubated with SIN-1, a peroxynitrite donor, (50 microM for 3 h) resulting in a nitrotyrosine content comparable to that seen in the ischemic/reperfused heart and causing significant cardiomyocyte apoptosis (P<0.01). Treatment with rhTrx markedly decreased SIN-1 induced apoptosis (P<0.01). CONCLUSIONS AND IMPLICATIONS These results demonstrate that Trx is a novel anti-apoptotic and cardioprotective molecule that exerts its cardioprotective effects by reducing ischemia/reperfusion-induced oxidative/nitrative stress.
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Hu A, Jiao X, Gao E, Koch WJ, Sharifi-Azad S, Grunwald Z, Ma XL, Sun JZ. Chronic beta-adrenergic receptor stimulation induces cardiac apoptosis and aggravates myocardial ischemia/reperfusion injury by provoking inducible nitric-oxide synthase-mediated nitrative stress. J Pharmacol Exp Ther 2006; 318:469-75. [PMID: 16574780 DOI: 10.1124/jpet.106.102160] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study provides evidence that inducible nitric-oxide synthase (iNOS)-mediated nitrative stress plays a pivotal role in chronic beta-adrenergic receptor (AR) stimulation-induced cardiac damage. In mice, 14 days of isoproterenol (ISO) stimulation via an osmotic minipump induced an up-regulation of iNOS as evidenced by increases in mRNA, protein expression, and immunochemical staining of myocardial iNOS. Serum level of C-reactive protein, an inflammatory mediator, was also markedly increased. Under chronic ISO stimulation, the up-regulated iNOS produced a significantly increased amount of nitric oxide (NO) and its byproduct, peroxynitrite, in the circulation and heart and subsequently resulted in an accelerated myocardial apoptosis. Forty-minute myocardial ischemia (MI) and 24-h reperfusion (R) further increased NO production and peroxynitrite formation and resulted in an enlarged infarct size in mice receiving chronic ISO stimulation. However, the treatment with a selective iNOS inhibitor [N-(3-(aminomethyl) benzyl)acetamidine] (1400W) or the use of a genetic modified animal (iNOS-knockout mice) markedly reduced iNOS-mediated production of NO and formation of peroxynitrite and consequently significantly decreased myocardial apoptosis and infarct size, showing a crucial link between iNOS-mediated nitrative stress and myocardial injury. In conclusion, chronic beta-AR stimulation up-regulates iNOS expression and increases NO production in the heart, which subsequently markedly enhances formation of reactive nitrogen species/peroxynitrite in the heart, thereby eliciting myocardial apoptosis and potentiating MI/R injury.
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Li DY, Tao L, Liu H, Christopher TA, Lopez BL, Ma XL. Role of ERK1/2 in the anti-apoptotic and cardioprotective effects of nitric oxide after myocardial ischemia and reperfusion. Apoptosis 2006; 11:923-30. [PMID: 16547595 DOI: 10.1007/s10495-006-6305-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Experimental results from cultured cells suggest that there is cross-talk between nitric oxide (NO) and extracellular signal-regulated kinase (ERK) in their anti-apoptotic effect. However, the cross-talk between these two molecules in either direction has not been confirmed in the whole organ or whole animal level. The aim of the present study was to determine whether ERK may play a role in the anti-apoptotic and cardioprotective effects of NO in myocardial ischemia/reperfusion (MI/R). METHODS Isolated perfused mouse hearts were subjected to 20 min of global ischemia and 120 min of reperfusion and treated with vehicle or an NO donor (SNAP, 10 muM) during reperfusion. To determine the role of ERK1/2 in the anti-apoptotic and cardioprotective effects of NO, hearts were pre-treated (10 min before ischemia) with U0126, a selective MEK1/2 inhibitor (1 muM). RESULTS Treatment with SNAP exerted significant cardioprotective effects as evidenced by reduced cardiac apoptosis (TUNEL and caspase 3 activity, p < 0.01), and improved cardiac functional recovery (p < 0.01). In addition, treatment with SNAP resulted in a 2.5-fold increase in ERK activation when compared with heart receiving vehicle. Pre-treatment with U0126 slightly increased post-ischemic myocardial apoptosis but had no significant effect on cardiac functional recovery in this isolated perfused heart model. However, treatment with U0126 completely blocked SNAP-induced ERK activation and markedly, although not completely, inhibited the cardioprotection exerted by SNAP. CONCLUSION These results demonstrate that nitric oxide exerts its anti-apoptotic and cardioprotective effects, at least in part, by activation of ERK in ischemic/reperfused heart.
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