Evaluation of the Differences of Myocardial Fibers between Acute and Chronic Myocardial Infarction: Application of Diffusion Tensor Magnetic Resonance Imaging in a Rhesus Monkey Model

Yuqing Wang,Wei Cai,Lei Wang,Rui Xia,Wei Chen,Jie Zheng,Fabao Gao 대한영상의학회 2016 Korean Journal of Radiology Vol.17 No.5

Objective: To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Materials and Methods: Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Results: Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 x 10-4 mm2/s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 x 10-4mm2/s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°–11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°–53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°–66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°–64.9 ± 4.3°). Conclusion: Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey’s models.

New dammarane-type triterpenoids from the leaves of Panax notoginseng and their protein tyrosine phosphatase 1B inhibitory activity

Li, Dawei,Cao, Jiaqing,Bi, Xiuli,Xia, Xichun,Li, Wei,Zhao, Yuqing The Korean Society of Ginseng 2014 Journal of Ginseng Research Vol.38 No.1

Background: Panax notoginseng has been used as a general tonic agent to invigorate human body for millennia in China and continued to be used until present. Methods: Some chromatographic methods were performed to isolate pure triterpenoids, and their structures were determined by nuclear magnetic resonance (NMR) experiments. Anti-diabetes activities of isolated compounds were evaluated through their inhibitory activity of protein tyrosine phosphatase 1B (PTP1B) enzyme. Results and Conclusion: Three new dammarane-type triterpenoids, notoginsenoside-LX (1), notoginsenoside-LY (2), and notoginsenoside-FZ (3) together with eighteen known compounds were isolated from the Panax notoginseng leaves. The structure-activity relationship of the compounds with dammaranetype triterpenoids and their PTP1B inhibitory activity were also reported. Results showed that compounds 2, 15, 20, and 21 can significantly inhibit the enzyme activity of PTP1B in a dose-dependent manner, with inhibitory concentration 50 ($IC_{50}$) values of $29.08{\mu}M$, $21.27{\mu}M$, $28.12{\mu}M$, and $26.59{\mu}M$, respectively. The results suggested that Panax notoginseng leaves might have potential as a new therapeutic agent for the treatment of diabetes.

New dammarane-type triterpenoids from the leaves of Panax notoginseng and their protein tyrosine phosphatase 1B inhibitory activity

Dawei Li,Jiaqing Cao,Xiuli Bi,Xichun Xia,Wei Li,Yuqing Zhao 고려인삼학회 2014 Journal of Ginseng Research Vol.38 No.1

Background: Panax notoginseng has been used as a general tonic agent to invigorate human body for millennia in China and continued to be used until present. Methods: Some chromatographic methods were performed to isolate pure triterpenoids, and their structures were determined by nuclear magnetic resonance (NMR) experiments. Anti-diabetes activities of isolated compounds were evaluated through their inhibitory activity of protein tyrosine phosphatase 1B (PTP1B) enzyme. Results and Conclusion: Three new dammarane-type triterpenoids, notoginsenoside-LX (1), notoginsenoside-LY (2), and notoginsenoside-FZ (3) together with eighteen known compounds were isolated from the Panax notoginseng leaves. The structure-activity relationship of the compounds with dammaranetype triterpenoids and their PTP1B inhibitory activity were also reported. Results showed that compounds 2, 15, 20, and 21 can significantly inhibit the enzyme activity of PTP1B in a dose-dependent manner, with inhibitory concentration 50 (IC50) values of 29.08 mM, 21.27 μM, 28.12 μM, and 26.59 μM, respectively. The results suggested that Panax notoginseng leaves might have potential as a new therapeutic agent for the treatment of diabetes.

Inhibition of miR-146a-5p and miR-8114 in Insulin-Secreting Cells Contributes to the Protection of Melatonin against Stearic Acid-Induced Cellular Senescence by Targeting Mafa

Shenghan Su,Qingrui Zhao,Lingfeng Dan,Yuqing Lin,Xuebei Li,Yunjin Zhang,Chunxiao Yang,Yimeng Dong,Xiaohan Li,Romano Regazzi,Changhao Sun,Xia Chu,Huimin Lu 대한내분비학회 2022 Endocrinology and metabolism Vol.37 No.6

Background: Chronic exposure to elevated levels of saturated fatty acids results in pancreatic β-cell senescence. However, targets and effective agents for preventing stearic acid-induced β-cell senescence are still lacking. Although melatonin administration can protect β-cells against lipotoxicity through anti-senescence processes, the precise underlying mechanisms still need to be explored. Therefore, we investigated the anti-senescence effect of melatonin on stearic acid-treated mouse β-cells and elucidated the possible role of microRNAs in this process. Methods: β-Cell senescence was identified by measuring the expression of senescence-related genes and senescence-associated β-galactosidase staining. Gain- and loss-of-function approaches were used to investigate the involvement of microRNAs in stearic acid-evoked β-cell senescence and dysfunction. Bioinformatics analyses and luciferase reporter activity assays were applied to predict the direct targets of microRNAs. Results: Long-term exposure to a high concentration of stearic acid-induced senescence and upregulated miR-146a-5p and miR-8114 expression in both mouse islets and β-TC6 cell lines. Melatonin effectively suppressed this process and reduced the levels of these two miRNAs. A remarkable reversibility of stearic acid-induced β-cell senescence and dysfunction was observed after silencing miR-146a-5p and miR-8114. Moreover, V-maf musculoaponeurotic fibrosarcoma oncogene homolog A (Mafa) was verified as a direct target of miR-146a-5p and miR-8114. Melatonin also significantly ameliorated senescence and dysfunction in miR-146a-5pand miR-8114-transfected β-cells. Conclusion: These data demonstrate that melatonin protects against stearic acid-induced β-cell senescence by inhibiting miR-146a-5p and miR-8114 and upregulating Mafa expression. This not only provides novel targets for preventing stearic acid-induced β-cell dysfunction, but also points to melatonin as a promising drug to combat type 2 diabetes progression.

In situ Copolymerized Toughened Polymethyl Methacrylate (PMMA) with Highly Transparency for Support Film of Polarizers

Yingying Wang,Bin Yang,Liangyong He,Yuqing Yang,Nuo Zhang,Yang Wang,Zhiqiang Shi,Yuchao Ke,Lifen Su,Jia-Sheng Qian,RU XIA,Tao Jiang 한국고분자학회 2022 폴리머 Vol.46 No.5

In this study, a series of poly(methyl methacrylate) (PMMA) copolymer films were prepared via solutionpolymerization of methyl methacrylate (MMA) with butyl acrylate (BA) and lauryl methacrylate (LMA) as monomers. Mechanical properties, hydrophobic properties, and optical properties of the films were intensively investigated. The rheological results showed that the fluidity of the copolymer was considerably enhanced. When the monomer ratio ofMMA:BA:LMA was 100:30:10, the copolymer film S4 showed the best overall performance with perfect optical transparency maintained. The results of the dynamic mechanical and thermal analysis suggested that the glass transition temperature (Tg) moved towards lower temperature, with enhanced ductility of the PMMA films. A large number of yieldfolds and crazes appeared on the cross-sectional surface of copolymer films through morphological observations, displaying the obvious characteristics of toughness fracture and obeying the energy dissipation mechanism of cracks shearband. The present study provided a facile way of preparing PMMA films with high toughness and light transmittanceby appropriate selection of the monomers, which will be of practical significance for further studies on the replacementof triacetyl cellulose as a support film of polarizers.

Identification and differential expression analysis of anthocyanin biosynthetic genes in root-skin color variants of radish (Raphanus sativus L.)

Rugang Yu,Xueling Du,Jing Li,Lan Liu,Chaomeng Hu,Xiaoling Yan,Yuqing Xia,Huijuan Xu 한국유전학회 2020 Genes & Genomics Vol.42 No.4

Background Taproot skin color is a major trait for assessing the commercial and nutritional quality of radish, and red-skinned radish is confirmed to improve consumer’s interest and health. However, little is known about the molecular mechanisms responsible for controlling the formation of red-skinned radish. Objective This study aimed to identify the differentially expressed anthocyanin biosynthetic genes between red- and whiteskinned radishes and understand the molecular regulatory mechanism underlying red-skinned radish formation. Methods Based on the published complete genome sequence of radish, the digital gene expression profiles of Yangzhouyuanbai (YB, white-skinned) and Sading (SD, red-skinned) were analyzed using Illumina sequencing. Results A total of 3666 DEGs were identified in SD compared with YB. Interestingly, 46 genes encoded enzymes related to anthocyanin biosynthesis and 241 genes encoded transcription factors were identified. KEGG pathway analysis showed that the formation of red-skinned radish was mainly controlled by pelargonidin-derived anthocyanin biosynthetic pathway genes. This process included the upregulation of PAL, C4H, 4CL, CHS, CHI, F3H, DFR, LDOX, and UGT enzymes in SD. CHS genes were specifically expressed in SD, and it might be the key point for red pigment accumulation in red-skinned radish. Furthermore, MYB1/2/75, bHLH (TT8), and WD 40 showed higher expression in SD than in YB. Meanwhile, the corresponding low-abundance anthocyanin biosynthesis enzymes and upregulation of MYB4 might be the factors influencing the formation of white-skinned radish. Conclusion These findings provide new insights into the molecular mechanisms and regulatory network of anthocyanin biosynthesis in red-skinned radish.