Autophagy Inhibition Promotes Gambogic Acid-induced Suppression of Growth and Apoptosis in Glioblastoma Cells

Luo, Guo-Xuan,Cai, Jun,Lin, Jing-Zhi,Luo, Wei-Shi,Luo, Heng-Shan,Jiang, Yu-Yang,Zhang, Yong Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Objective: To investigate the effects of gambogic acid (GA) on the growth of human malignant glioma cells. Methods: U251MG and U87MG human glioma cell lines were treated with GA and growth and proliferation were investigated by MTT and colony formation assays. Cell apoptosis was analyzed by annexin V FITC/PI flow cytometry, mitochondrial membrane potential assays and DAPI nuclear staining. Monodansylcadaverine (MDC) staining and GFP-LC3 localisation were used to detect autophagy. Western blotting was used to investigate the molecular changes that occurred in the course of GA treatment. Results: GA treatment significantly suppressed cell proliferation and colony formation, induced apoptosis in U251 and U87MG glioblastoma cells in a time- and dose-dependent manner. GA treatment also lead to the accumulation of monodansylcadaverine (MDC) in autophagic vacuoles, upregulated expressions of Atg5, Beclin 1 and LC3-II, and the increase of punctate fluorescent signals in glioblastoma cells pre-transfected with GFP-tagged LC3 plasmid. After the combination treatment of autophagy inhitors and GA, GA mediated growth inhibition and apoptotic cell death was further potentiated. Conclusion: Our results suggested that autophagic responses play roles as a self-protective mechanism in GA-treated glioblastoma cells, and autophagy inhibition could be a novel adjunctive strategy for enhancing chemotherapeutic effect of GA as an anti-malignant glioma agent.

A Single Chord Localization Algorithm for Wireless Sensor Networks

Yong-Luo Shen,Yuan Zhang,Yu-Ping Hu,Jun Zhang 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

This paper presents a novel range-free single chord localization algorithm with low energy consumption and high accuracy for wireless sensor networks. A mobile anchor node and a mobile reference node are employed to periodically broadcast beacon messages and reference messages, respectively. Each sensor node is equipped with a received signal strength indicator for comparing the signal strength. By using the edge function and the result of comparing signal strength, each sensor node only needs one chord on the communication circle for localization. Compared with previous approaches that require multiple chords, less beacon messages are required by the sensor nodes. In the proposed algorithm, the localization error mainly depends on the move distance interval. However, for the other approaches, large localization errors can be observed according to the angle between chords which may descend the localization accuracy dramatically. Analysis results indicate that the proposed algorithm is superior to other approaches in energy consumption and localization accuracy.

Microstructure evolution and effect on deuterium retention in oxide dispersion strengthened tungsten during He⁺ irradiation

Ding, Xiao-Yu,Xu, Qiu,Zhu, Xiao-yong,Luo, Lai-Ma,Huang, Jian-Jun,Yu, Bin,Gao, Xiang,Li, Jian-Gang,Wu, Yu-Cheng Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.12

Oxide dispersion-strengthened materials W-1wt%Pr₂O₃ and W-1wt%La₂O₃ were synthesized by wet chemical method and spark plasma sintering. The field emission scanning electron microscopy (FE-SEM) analysis, XRD and Vickers microhardness measurements were conducted to characterize the samples. The irradiations were carried out with a 5 keV helium ion beam to fluences up to 5.0 × 10²¹ ions/m² under 600 ℃ using the low-energy ion irradiation system. Transmission electron microscopy (TEM) study was performed to investigate the microstructural evolution in W-1wt%Pr₂O₃ and W-1wt%La₂O₃. At 1.0 × 10²⁰ He⁺/m², the average loops size of the W-1wt%Pr₂O₃ was 4.3 nm, much lower than W-1wt% La₂O₃ of 8.5 nm. However, helium bubbles were not observed throughout in both doped W materials. The effects of pre-irradiation with 1.0 × 10²¹ He⁺/m² on trapping of injected deuterium in doped W was studied by thermal desorption spectrometry (TDS) technique using quadrupole mass spectrometer. Compared with the samples without He⁺ pre-irradiation, deuterium (D) retention of doped W materials increased after He⁺ irradiation, whose retention was unsaturated at the damage level of 1.0 × 10²²D₂⁺/m². The present results implied that irradiation effect of He⁺ ions must be taken into account to evaluate the deuterium retention in fusion material applications.

The differences between copper sulfate and tribasic copper chloride on growth performance, redox status, deposition in tissues of pigs, and excretion in feces

Zheng, Ping,Pu, Bei,Yu, Bing,He, Jun,Yu, Jie,Mao, Xiangbing,Luo, Yuheng,Luo, Junqiu,Huang, Zhiqing,Luo, Chenggui,Wang, Shaohui,Chen, Daiwen Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.6

Objective: The objective of this experiment was to compare the effects of adding 130 mg/kg Cu from either copper sulfate (CS) or tribasic copper chloride (TBCC) on growth performance, mineral deposition in tissues, and the excretion in feces of pigs as well as changes in the mineral contents in tissues and feces when the supplemental Cu level was decreased from 130 mg/kg to 10 mg/kg. Methods: A total of 72 pigs ($32.6{\pm}1.2kg$) were randomly assigned to a CS diet or a TBCC diet with 6 pens per treatment. The trial lasted 102 d and included 3 phases (phase 1, 1 to 30 d; phase 2, 31 to 81 d; and phase 3, 82 to 102 d). The supplemental levels of Cu in the 2 treatments were 130 mg/kg in phase 1 and 2 and 10 mg/kg in phase 3. Results: The results showed that pigs fed the CS diet tended to have higher average daily gain than pigs fed the TBCC diet during d 1 to 81 (p<0.10). Compared with CS, TBCC increased the activities of aspartate transaminase (AST), ceruloplasmin, and superoxide dismutase in serum on d 30 (p<0.05). The TBCC decreased the Cu level in the liver on d 81 (p<0.05) and increased the Mn level in the liver on d 102 (p<0.05). The concentration of Cu in feces sharply decreased when the supplemental Cu level in diet changed from 130 mg/kg to 10 mg/kg in both diets (p<0.05). Conclusion: The result suggested that TBCC and CS had no significant difference on growth performance but TBCC had higher activities of AST and antioxidant enzymes and lower liver Cu than CS when pigs fed diets with 130 mg Cu /kg diet.

Nicotine exacerbates tacrolimus-induced renal injury by programmed cell death

( Yu Ji Jiang ),( Sheng Cui ),( Kang Luo ),( Jun Ding ),( Qi Yan Nan ),( Shang Guo Piao ),( Mei Ying Xuan ),( Hai Lan Zheng ),( Yong Jie Jin ),( Ji Zhe Jin ),( Jung Pyo Lee ),( Byung Ha Chung ),( Bum 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.6

Background/Aims: Cigarette smoking is an important modifiable risk factor in kidney disease progression. However, the underlying mechanisms for this are lacking. This study aimed to assess whether nicotine (NIC), a major toxic component of cigarette smoking, would exacerbates tacrolimus (TAC)-induced renal in-jury. Methods: Sprague-Dawley rats were treated daily with NIC, TAC, or both drugs for 4 weeks. The influence of NIC on TAC-caused renal injury was examined via renal function, histopathology, oxidative stress, mitochondria, endoplasmic reticulum (ER) stress, and programmed cell death (apoptosis and autophagy). Results: Both NIC and TAC significantly impaired renal function and histopathology, while combined NIC and TAC treatment aggravated these parameters beyond the effects of either alone. Increased oxidative stress, ER stress, mitochondrial dysfunction, proinflammatory and profibrotic cytokine expressions, and programmed cell death from either NIC or TAC were also aggravated by the two combined. Conclusions: Our observations suggest that NIC exacerbates chronic TAC nephrotoxicity, implying that smoking cessation may be beneficial for transplant smokers taking TAC.

Autophagy induced by H. pylori VacA regulated the survival mechanism of the SGC7901 human gastric cancer cell line

Luo Juan,Bai Luyan,Tao Jun,Wen Yu,Li Mingke,Zhu Yunzhen,Luo Sufeng,Pu Guangyu,Ma Lanqing 한국유전학회 2021 Genes & Genomics Vol.43 No.10

Background Vacuolating cytotoxin (VacA) is an important virulence factor of Helicobacter pylori (H. pylori). It was previously believed that VacA can trigger the cascade of apoptosis on mitochondria to lead to cell apoptosis. Recently, it was found that VacA can induce autophagy. However, the molecular mechanism by which VacA induces autophagy is largely unknown. Objective We aimed to explore the molecular mechanism of autophagy induced by H. pylori in gastric cancer cells and the efect of autophagy on the survival of gastric cancer cells. Methods The autophagy of human gastric cancer cell line SGC7901 was detected by Western blot and RT-PCR in the treatment of VacA protein of H. pylori. The relationship between autophagy and reactive oxygen species (ROS) in the proliferation of gastric cancer cells were studied by gene expression silences (siRNA) and CM-H2DCFDA (DCF) staining. Results The results showed that VacA protein secreted by H. pylori in the supernatant stimulated autophagy in SGC7901 cells. After VacA protein treatment, the mRNA expressions of BECN1, ATG7 and PIK3C3, were up-regulated. ATG7 silencing by siRNA inhibited VacA-induced autophagy. Furthermore, our data demonstrated that VacA protein increased ROS levels. Addition of the antioxidant N-acetyl-l-cysteine (NAC) suppressed the levels of ROS, leading to inhibition of autophagy. Conclusions H. pylori VacA is a key toxin that induces autophagy by increased ROS levels. And our fndings demonstrated that VacA signifcantly inhibited proliferation in SGC7901 cells.

Aflatoxin B1 Promotes Cell Growth and Invasion in Hepatocellular Carcinoma HepG2 Cells through H19 and E2F1

Lv, Jun,Yu, Ya-Qun,Li, Shu-Qun,Luo, Liang,Wang, Qian Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

H19 is an imprinted oncofetal gene, and loss of imprinting at the H19 locus results in over-expression of H19 in cancers. Aflatoxin B1(AFB1) is regarded as one of the most dangerous carcinogens. Exposure to AFB1 would most easily increase susceptibility to diseases such as hepatocellular carcinoma(HCC) but any possible relationship between AFB1 and H19 is not clear. In present study, we found that AFB1 could up-regulate the expression of H19 and promote cell growth and invasion by hepatocellular carcinoma HepG2 cells. Knocking down H19 RNA co ld reverse the effects of AFB1 on cell growth and invasion. In addition, AFB1 induced the expression of E2F1 and its knock-down could down-regulate H19 expression and suppress cell growth and invasion in hepatocellular carcinoma HepG2 cells. Furthermore, E2F1 over-expression could up-regulate H19 expression and promote cell growth and invasion, with binding to the H19 promoter being demonstrated by chromatin immunoprecipitation assays (ChIP). In summary, our results suggested that aflatoxin B1could promote cell growth and invasion in hepatocellular carcinoma HepG2 cells through actions on H19 and E2F1.

Morphology and Molecular Characteristics of Alternaria sonchi Causing Brown Leaf Spot on Sonchus asper in Korea

Huan Luo,Myung Soo Park,Jun Myoung Yu 한국식물병리학회 2021 식물병연구 Vol.27 No.3

During a disease survey on weeds and minor cultivated crops in Korea, a brown leaf spot disease was ob- served on Sonchus asper. Leaf lesions were round or irregular in shape, and grayish brown to brown with a purple margin. In severe infection, lesions enlarged and coalesced, resulting in blighting of the leaves. The isolates from these leaf lesions were identified as Alternaira sonchi based on morphological characteristics and phylogenetic analyses of Internal transcribed spacer region, Alternaria allergen a1, glyceraldehyde 3-phosphate dehydrogenase, RNA polymerase II, and translation elongation factor genes. This study pro- vides a comprehensive description of the morphological characteristics and phylogenetical traits of A. sonchi causing brown leaf spot on S. asper in Korea.

Identification and comparative analysis of piRNAs in ovary and testis of Nile tilapia (Oreochromis niloticus)

Fan Yu,Xi Gan,Yi Zhou,Huan Zhong,Jun Xiao,Jinpeng Yan,Yongju Luo 한국유전학회 2016 Genes & Genomics Vol.38 No.6

It has been shown that piRNA is the largest class of small non-coding RNA in germline cells of animals which plays key roles in transposons regulation and transcriptional activities. In the present study, piRNAs from two small RNA libraries including ovary and testis of Nile tilapia were identified and characterized. By length and k-mer based small RNA prediction algorithm, 279,059 and 583,230 small RNA reads were confirmed as piRNA from ovary and testis, respectively. The identified piRNAs showed evolutionarily conserved characterization, such as uridine bias in the 50 ends. The 142,961 and 296,775 piRNAs from ovary and testis were mapped to the draft assembly of the tilapia genome, respectively. Both ovary and testis piRNAs were enriched from linkage (LG)6 and LG7. Meanwhile, the even distribution of ?strand and -strand suggested the Ping–pong pathway (a double-displacement reaction of ?strand and -strand) hypothesis. These piRNAs were derived from the upstream -2 kb and downstream ?2 kb as well as gene regions which suggested a regulatory function on transcription activities. In gene regions, abundant piRNAs were derived from 50UTR, 30UTR and CDS. Furthermore, we characterized the differentially expressed piRNAs between ovary and testis. In total, 1979 and 2453 piRNAs were significantly higher and lower expressed in ovary compared to that in testis, respectively. Thereinto, the most concentrated up-regulate and down-regulate piRNAs were both from serine/threonine– protein kinase PIM genes of different transcripts. These findings will be helpful to facilitate studies on the piRNAs regulation on genes during gonad development of teleosts.

Synthesis of Porous Carbon Supported Palladium Nanoparticle Catalysts by Atomic Layer Deposition: Application for Rechargeable Lithium–O₂ Battery

Lei, Yu,Lu, Jun,Luo, Xiangyi,Wu, Tianpin,Du, Peng,Zhang, Xiaoyi,Ren, Yang,Wen, Jianguo,Miller, Dean J.,Miller, Jeffrey T.,Sun, Yang-Kook,Elam, Jeffrey W.,Amine, Khalil American Chemical Society 2013 Nano letters Vol.13 No.9

<P>In this study, atomic layer deposition (ALD) was used to deposit nanostructured palladium on porous carbon as the cathode material for Li–O<SUB>2</SUB> cells. Scanning transmission electron microscopy showed discrete crystalline nanoparticles decorating the surface of the porous carbon support, where the size could be controlled in the range of 2–8 nm and depended on the number of Pd ALD cycles performed. X-ray absorption spectroscopy at the Pd K-edge revealed that the carbon supported Pd existed in a mixed phase of metallic palladium and palladium oxide. The conformality of ALD allowed us to uniformly disperse the Pd catalyst onto the carbon support while preserving the initial porous structure. As a result, the charging and discharging performance of the oxygen cathode in a Li–O<SUB>2</SUB> cell was improved. Our results suggest that ALD is a promising technique for tailoring the surface composition and structure of nanoporous supports in energy storage devices.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2013/nalefd.2013.13.issue-9/nl401833p/production/images/medium/nl-2013-01833p_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl401833p'>ACS Electronic Supporting Info</A></P>