Grub polypeptide extracts protect against oxidative stress through the NRF2-ARE signaling pathway

Jingyang Chen,Yingjian Sun,Shan Huang,Hong Shen,Yongjie Chen 한국통합생물학회 2021 Animal cells and systems Vol.25 No.6

Grub polypeptide extracts (GPEs) have antioxidant effects; however, their underlying molecular mechanisms are unknown. This study explored the antioxidant molecular mechanism of GPE via the nuclear factor-erythroid 2-related factor 2 (NRF2)-antioxidant response element (ARE) signaling pathway in C2C12 muscle satellite cells exposed to oxidative stress. The effects of GPE/or H2O2 on C2C12 were investigated by the MTT (3- (4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide) viability assay and immunofluorescence and small interfering RNA (siRNA) analyses. The cell viability, cell damage, intracellular reactive oxygen species (ROS) levels, and NRF2 signaling pathways related to proteins were measured. GPE significantly increased the antioxidant capacity of cells, evident by increased cell viability and decreased lactate dehydrogenase leakage, DNA damage, malondialdehyde content, and ROS level. GPE also markedly increased mRNA expression levels and activities of antioxidant enzymes including superoxidase 1 and 2, catalase, and glutathione peroxidase. In addition, GPE increased the gene and protein expression of NRF2 and heme oxygenase 1 by promoting NRF2 translocation from the cytoplasm to the nucleus and activating NRF2-ARE signaling pathways. The antioxidant effects of GPE through these signaling pathways were further confirmed by NRF2-specific siRNA silencing. Thus, GPE enhances antioxidant capacity and alleviates oxidative damage of C2C12 cells via the NRF2-ARE signaling pathway.

Progresses on the Optimal Processing and Properties of Highly Porous Rare Earth Silicate Thermal Insulators

Wu, Zhen,Sun, Luchao,Wang, Jingyang The Korean Ceramic Society 2018 한국세라믹학회지 Vol.55 No.6

High-temperature thermal insulation materials challenge extensive oxide candidates such as porus $SiO_2$, $Al_2O_3$, yttria-stabilized zirconia, and mullite, due to the needs of good mechanical, thermal, and chemical reliabilities at high temperatures simultaneously. Recently, porous rare earth (RE) silicates have been revealed to be excellent thermal insulators in harsh environments. These materials display attractive properties, including high porosity, moderately high compressive strength, low processing shrinkage (near-net-shaping), and very low thermal conductivity. The current critical challenge is to balance the excellent thermal insulation property (extremely high porosity) with their good mechanical properties, especially at high temperatures. Herein, we review the recent developments in processing techniques to achieve extremely high porosity and multiscale strengthening strategy, including solid solution strengthening and fiber reinforcement methods, for enhancing the mechanical properties of porous RE silicate ceramics. Highly porous RE silicates are highlighted as emerging high-temperature thermal insulators for extreme environments.

Isolation and Characterization of Plant Growth-Promoting Rhizobacteria from Wheat Roots by Wheat Germ Agglutinin Labeled with Fluorescein Isothiocyanate

Jian Zhang,Jingyang Liu,Liyuan Meng,Zhongyou Ma,Xinyun Tang,Yuanyuan Cao,Leni Sun 한국미생물학회 2012 The journal of microbiology Vol.50 No.2

Thirty-two isolates were obtained from wheat rhizosphere by wheat germ agglutinin (WGA) labeled with fluorescein isothiocyanate (FITC). Most isolates were able to produce indole acetic acid (65.6%) and siderophores (59.3%), as well as exhibited phosphate solubilization (96.8%). Fourteen isolates displayed three plant growth-promoting traits. Among these strains, two phosphate-dissolving ones, WS29 and WS31, were evaluated for their beneficial effects on the early growth of wheat (Triticum aestivum Wan33). Strain WS29and WS31 significantly promoted the development of lateral roots by 34.9% and 27.6%, as well as increased the root dry weight by 25.0% and 25.6%, respectively, compared to those of the control. Based on 16S rRNA gene sequence comparisons and phylogenetic positions, both isolates were determined to belong to the genus Bacillus. The proportion of isolates showing the properties of plant growth-promoting rhizobacteria (PGPR) was higher than in previous reports. The efficiency of the isolation of PGPR strains was also greatly increased by WGA labeled with FITC. The present study indicated that WGA could be used as an effective tool for isolating PGPR strains with high affinity to host plants from wheat roots. The proposed approach could facilitate research on biofertilizers or biocontrol agents.

Synthesis of novel oleanolic acid and ursolic acid in C-28 position derivatives as potential anticancer agents

Tian Tian,Xinyu Liu,이응석,Jingyang Sun,Zhonghua Feng,Long-Xuan Zhao,Chunhui Zhao 대한약학회 2017 Archives of Pharmacal Research Vol.40 No.4

A series of nitrogen-containing derivatives ofoleanolic acid and ursolic acid were prepared by a modificationat C-28 position via esterification with 2-hydroxyaceticacid followed by amidation with amines, such aspiperazine, N-methylpiperazine, and alkane-1, 2-diamines,alkane-1, 4-diamines, alkane-1, 6-diamines. In vitroantiproliferative activities of the compounds preparedtowards MCF-7, Hela and A549 cell lines were evaluatedby a MTT method to show that OA-5a, OA-5b, OA-5c andUA-5a showed somewhat improved antiproliferativeactivities against MCF-7, Hela and A549 cells comparingto that of the positive control, gefitinib.

Taurocholic acid promotes hepatic stellate cell activation via S1PR2/p38 MAPK/YAP signaling under cholestatic conditions

Jing Yang,Xujiao Tang,Zhu Liang,Mingzhu Chen,Lixin Sun 대한간학회 2023 Clinical and Molecular Hepatology(대한간학회지) Vol.29 No.2

Background/Aims: Disrupted bile acid regulation and accumulation in the liver can contribute to progressive liver damage and fibrosis. However, the effects of bile acids on the activation of hepatic stellate cells (HSCs) remain unclear. This study investigated the effects of bile acids on HSC activation during liver fibrosis, and examined the underlying mechanisms. Methods: The immortalized HSCs, LX-2 and JS-1cells were used for the in vitro study. in vitro, the adeno-associated viruses adeno-associated virus-sh-S1PR2 and JTE-013 were used to pharmacologically inhibit the activity of S1PR2 in a murine model of fibrosis induced by a 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet. Histological and biochemical analyses were performed to study the involvement of S1PR2 in the regulation of fibrogenic factors as well as the activation properties of HSCs. Results: S1PR2 was the predominant S1PR expressed in HSCs and was upregulated during taurocholic acid (TCA) stimulation and in cholestatic liver fibrosis mice. TCA-induced HSC proliferation, migration and contraction and extracellular matrix protein secretion were inhibited by JTE-013 and a specific shRNA targeting S1PR2 in LX-2 and JS-1 cells. Meanwhile, treatment with JTE-013 or S1PR2 deficiency significantly attenuated liver histopathological injury, collagen accumulation, and the expression of fibrogenesis-associated genes in mice fed a DDC diet. Furthermore, TCAmediated activation of HSCs through S1PR2 was closely related to the yes-associated protein (YAP) signaling pathway via p38 mitogen-activated protein kinase (p38 MAPK). Conclusions: TCA-induced activation of the S1PR2/p38 MAPK/YAP signaling pathways plays a vital role in regulating HSC activation, which might be therapeutically relevant for targeting cholestatic liver fibrosis.

Construction of graphene/AuNPs based amperometric immunosensor for detecting bladder cancer biomarker apolipoprotein A1

Jing Yang,Wang Xingyuan,Zhou Tingting,Wei Liangjun,Guo Meiling,Liu Yanan,Sun Xiaoqi,Wang Yanjie 한국탄소학회 2024 Carbon Letters Vol.34 No.3

This paper presents the construction and characterization of an amperometric immunosensor based on the graphene/gold nanoparticles (AuNPs/GO) nanocomposite for the detection of the bladder cancer biomarker, apolipoprotein A1 (Apo-A1). The morphological analysis of the AuNPs/GO nanocomposite demonstrated an almost spherical shape of AuNPs and the successful coverage of their surface by graphene oxide. An increased G peak and decreased D peak after the association of AuNPs with GO, implied a reduction in graphene defects. The X-ray photoelectron spectroscopy (XPS) indicated a significant decrease in the quantity of oxygen-containing functional groups in the AuNPs/GO nanocomposite, as compared to the original GO. Furthermore, the developed sensor demonstrated commendable sensitivity and selectivity, with a wide linear range for Apo-A1 detection. Importantly, the immunosensor exhibited remarkable stability over a period of 14 days, signifying its potential for practical applications.