Protective Effect of Magnolol on TBHP-Induced Injury in H460 Cells Partially via a p53 Dependent Mechanism

Hai-bo Li,Jian-mei Gao,Xi-xiang Ying,Shu-Peng Wang,Jian-chun Li 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.7

The aim is to investigate the effect of Magnolol preserved H460 cells from an oxidative agent tert-butylhydroperoxide (TBHP)-induced cell death. Magnolol augmented cell survival ratio after TBHP challenged. The protective action of this drug was more efficacious than that of Nacetylcysteine (NAC) which is a putative antioxidant. DNA damage, detected by the comet assay, was diminished after treatment of Magnolol. The cells viability decreased after treatment with 0.15 mM TBHP for 24 h, accompanied by inducing apoptotic death of the cells. Cytotoxicity and apoptosis induced by TBHP were significantly inhibited or attenuated after pretreatment with 20 µM Magnolol. Magnolol contributes to the cells survival through downregulated the p53 phosphorylation and PTEN expression, and upregulated Akt phosphorylation. Taken together, Magnolol was effective against DNA single strand breaks (SSB) formation, cytotoxicity and lipid peroxidation induced by TBHP, and its effects on p53 phosphorylation, PTEN and Akt phosphorylation were due to its antioxidative function, and partially via a p53 dependent mechanism in this protective effects.

Magnolol-Induced H460 Cells Death via Autophagy but Not Apoptosis

Li, Hai-Bo,Yi, Xin,Gao, Jian-Mei,Ying, Xi-Xiang,Guan, Hong-Quan,Li, Jian-Chun 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.12

We have reported that the protective effect of Magnolol on TBHP-induced injury in human non-small lung cancer H460 cells is partially via a p53 dependent mechanism. In this study, we found that Magnolol displayed a stimulatory effect at low concentrations $(\leq20{\mu}M)$ whilst inhibitory effect at high concentrations $(\geq20{\mu}M)$ in H460 cells. To investigate the mechanism of inducing the biphasic effect in H460 cells with Magnolol, we showed that Magnolol stimulated DNA synthesis at low concentrations and displayed an inhibition effect at high concentrations in H460 cells. More importantly, the inhibition of DNA synthesis was accompanied by the S phase cell cycle arrest and the appearance of intense intracytoplasmic vacuoles. These vacuoles can be labeled by autophagic marker monodansylcadaverin (MDC), 3-methyladenine (3-MA), an inhibitor of autophagy, was able to inhibit the occurrence of autophagy. The results of the LDH activity assay and TUNEL assay also showed that Magnolol at high concentrations inhibiting H460 cell growth was not via apoptotic pathway. Furthermore, accompanied by the occurrence of autophagy, the expression of phospho-Akt was down-regulated but PTEN significantly was up-regulated. In conclusion, Magnolol induces H460 cells death by autophagy but not apoptotic pathway. Blockade of PI3K/PTEN/Akt pathway is maybe related to Magnolol-induced autophagy. Autophagic cells death induction by Magnolol underlines the potential utility of its induction as a new cancer treatment modality.

Magnolol-Induced H460 Cells Death via Autophagy but Not Apoptosis

Hai-bo Li,Xin Yi,Jian-mei Gao,Xi-xiang Ying,Hong-quan Guan,Jian-chun Li 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.12

We have reported that the protective effect of Magnolol on TBHP-induced injury in human nonsmall lung cancer H460 cells is partially via a p53 dependent mechanism. In this study, we found that Magnolol displayed a stimulatory effect at low concentrations (≤20 µM) whilst inhibitory effect at high concentrations (≥40 µM) in H460 cells. To investigate the mechanism of inducing the biphasic effect in H460 cells with Magnolol, we showed that Magnolol stimulated DNA synthesis at low concentrations and displayed an inhibition effect at high concentrations in H460 cells. More importantly, the inhibition of DNA synthesis was accompanied by the S phase cell cycle arrest and the appearance of intense intracytoplasmic vacuoles. These vacuoles can be labeled by autophagic marker monodansylcadaverin (MDC), 3-methyladenine (3- MA), an inhibitor of autophagy, was able to inhibit the occurrence of autophagy. The results of the LDH activity assay and TUNEL assay also showed that Magnolol at high concentrations inhibiting H460 cell growth was not via apoptotic pathway. Furthermore, accompanied by the occurrence of autophagy, the expression of phospho-Akt was down-regulated but PTEN significantly was up-regulated. In conclusion, Magnolol induces H460 cells death by autophagy but not apoptotic pathway. Blockade of PI3K/PTEN/Akt pathway is maybe related to Magnololinduced autophagy. Autophagic cells death induction by Magnolol underlines the potential utility of its induction as a new cancer treatment modality.

Two new sesquiterpenoids from endophytic fungus J3 isolated from Mangrove Plant Ceriops tagal

Yan-Bo Zeng,Hai-Gang Gu,Wen-Jian Zuo,Li-Li Zhang,Hong-Jin Bai,Zhi-Kai Guo,Peter Proksch,Wen Li Mei,Hao Fu Dai 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.5

Two new sesquiterpenoids, named 2a-hydroxyxylaranolB (1) and 4b-hydroxyxylaranol B (2), togetherwith a known diterpenoid 3,4-seco-sonderianol (3) wereisolated from the fermentation of endophytic fungus J3 ofCeriops tagal. Their structures were elucidated based onspectroscopic methods including 1D and 2D NMR(HMQC, 1H-1H COSY and HMBC). All compounds wereevaluated for their cytotoxic activities by MTT method,and compound 3 exhibited cytotoxic activities againstK562, SGC-7901, and BEL-7402 cell lines.

Numerical simulation and experiments of magnetic flux leakage inspection in pipeline steel

Xun-Bo Li,Xiang Li,Liang Chen,Pei-Fu Feng,Hai-Dong Wang,Zuo-Ying Huang 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.1

The magnetic flux leakage (MFL) method is currently the most commonly used pipeline inspection technique. In this paper, numerical simulation and experimental investigation on defect inspection in pipeline steel using MFL were carried out. In theoretical analysis, typical three-dimensional (3D) defects were accurately modeled and detailed MFL signals in the test surface were calculated by 3D finite element method (FEM). To confirm the 3D FEM results, different artificial defects were made and the MFL experiments were performed. The experimental study demonstrated that the results were agreement with the 3D FEM result. The results show that the 3D FEM is an effective analysis method for pipeline steel MFL inspection.

Molecular cloning of the duck MEF2C gene cDNA coding domain sequence and its expression during fetal muscle tissue development

Ling-Li Sun,He-he Liu,Hao-han Wang,Jian-Ming Si,Hai-bo Jin,Xin-xin Li,Chao Yang,Liang Li,Jiwen Wang 한국유전학회 2013 Genes & Genomics Vol.35 No.3

Myogenic enhancer transcription factor 2c (MEF2c), one of the members of the MEF2 family of transcription factors, plays an important role in mammalian muscle development. However, the role of MEF2c in avian muscle development still remains unclear. To understand the function of MEF2c in avian muscle development, we first cloned the duck MEF2c coding domain sequence (CDS) and analyzed MEF2c expression in duck muscle tissues of embryos from 10 days of incubation to 1 week after birth using real-time PCR technology. The results showed that the duck MEF2c CDS consists of 1,398nucleotides that encode 465 amino acids. The MEF2c duck protein contains a MADS domain, a MEF2 domain and a HJURP_C domain with high homology to related proteins in other organisms. Different expression levels of MEF2c were found in skeletal, smooth and cardiac muscle. Therefore, these results indicated that duck MEF2c has two conserved domains (a MADS and a MEF2 domain), is an indispensable regulator of muscle development, and plays an important role in the development of duck muscle.

리그닌 함유 셀룰로오스 나노섬유로 강화된 폴리락틴산 나노복합재의 제조 및 분석

Hai Bo Sun,Xuan Wang,Li Ping Zhang 한국고분자학회 2014 폴리머 Vol.38 No.4

A chemo-mechanical method was used to prepare lignin-containing cellulose nanofibrils(L-CNF) from unbleached woodpulps dispersed uniformly in an organic solvent. L-CNF/PLA composites were obtained by solvent cast-ing method. The effects of L-CNF concentration on the composite performances were characterized by tensile test machine. contact angle machine, scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR). The tensile test results indicated that the tensile strength and elongation-at-break increased by 50.6%and 31.8% compared with pure PLA. The contact angle of PLA composites decreased from 79.3° to 68.9°. The FTIR analysis suc- cessfully showed that L-CNF had formed intermolecular hydrogen bonding with PLA matrix.

Dynamics of excitons and carriers at the NPB/C60 interface by transient photocurrents

Li Ping,De Yang Xiu,Wu Bo,Zhang Yu,Jiang Ze Zhuan,Bao Xi,Huang Hai Shen 한국물리학회 2020 Current Applied Physics Vol.20 No.5

The transient photocurrent (TPC) technique was performed to explore the dynamics of excitons and carriers at organic active layer/buffer layer interfaces. A special device with ITO/PEIE/NPB/C60/Al structure was designed to study the interfacial processes at the NPB/C60 interface. An external electrical field was provided to neutralize the built-in electrical field of the device. Interestingly, a new phenomenon was observed, wherein the polarity of the TPC changed from negative to positive under an external electrical field. The initial negative signal was ascribed to exciton separation by the built-in field in C60, and the subsequent positive signal can be attributed to the diffusion of electrons that accumulate at the NPB/C60 interface. TPC measurements shown that further increasing the external electrical field causes polarity to change twice. Analyzing the two changes in polarity revealed that the NPB did not only extract holes from C60 but also provided an effective interface for exciton dissociation.

Fabrication and Mössbauer Characterization of MgFe₂O₄/Fe₃O₄ Composite Nano-particles

LI Zhi-Wei,WANG Hai-Bo,SUN Jian-Rong,GAO Yuan,LI Fa-Shen 한국자기학회 2008 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Experimental study on fire performance of axially-restrained NSC and HSC columns

Bo Wu,Yi-Hai Li 국제구조공학회 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.32 No.5

This paper describes fire performance of eight axially restrained reinforced concrete (RC) columns under a combination of two different load ratios and two different axial restraint ratios. The eight RC columns were all concentrically loaded and subjected to ISO834 standard fire on all sides. Axial restraints were imposed at the top of the columns to simulate the restraining effect of the rest of the whole frame. The axial restraint was effective when the column was expanding as well as contracting. As the results of the experiments have shown, the stiffness of the axial restraint and load level play an important role in the fire behaviors of both HSC and NSC columns. It is found that (a) the maximum deformations during expanding phase were influenced mostly by load ratio and hardly by axial restraint ratio, (b) For a given load ratio, axial restraint ratio had a great impact on the development of axial deformation during contraction phase beyond the initial equilibrium state, (c) increasing the axial restraint increased the value of restraint force generated in both the NSC and HSC columns, and (d) the development of column axial force during the contracting and cooling phase followed nearly parallel trend for columns under the same load ratio.