272 results on '"Ming, Kang"'
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2. Retraction notice to 'Two new luminescent coordination polymers: Therapeutic effects on angina pectoris' [Arab. J. Chem. 15(2) (2022) 103566]
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Jing Li, Jing-Wei Yuan, Hai-Bo Yu, Yu-Ming Kang, and Qing-Feng Su
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Chemistry ,QD1-999 - Published
- 2023
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3. The Improvement and Application of the Geoelectrochemical Exploration Method
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Ming Kang, Huanzhao Guo, Wende Zhu, Xianrong Luo, and Jianwen Yang
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geoelectrochemical method ,dipole ,low voltage ,technique improvement ,concealed deposit ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The anionic and cationic species of elements from deeply buried deposits migrate to the near surface driven by various geological forces. The geoelectrochemical exploration method (GEM), derived from CHIM, consists of the application of an electric field to collect these active ions at the designated electrode. Prospecting effects have been investigated by researchers since the coming up of CHIM. However, the cumbersome technical equipment, complex techniques and low production efficiency have restricted its potential application in field geological survey. This paper presents the newly developed CHIM that is electrified by a low voltage dipole. The improved technique allows both anionic and cationic species of elements to be extracted simultaneously in an anode and in a cathode. Compared with the conventional CHIM method, the innovative techniques called dipole geoelectrochemical method are characterized by simple instrumentation, low cost and easy operation in field, and in particular enables simultaneous extraction of anionic and cationic species of elements, from which more information can be derived with higher extraction efficiency. The dipole geoelectrochemical method was proposed and applied in the experiments of the Yingezhuang gold ore from Zhaoyuan, Shandong Province, the 210 gold ore from Jinwozi, Xinjiang Province, and the Daiyinzhang gold polymetallic deposit from Wutaishan, Shanxi Province. There are clearly anomalies above the gold ore body, indicating the effectiveness and feasibility of the improved dipole geoelectrochemical method in both scientific research and mineral exploration. The results of anode extraction in several mining areas have shown good results, indicating that gold may be mainly negatively charged. In fact, many metal nanoparticles, clay minerals, or complexes of metal ions are negatively charged, so they migrate to the anode electrode and enrich.
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- 2023
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4. Two new luminescent coordination polymers: Therapeutic effects on angina pectoris
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Jing Li, Jing-Wei Yuan, Hai-Bo Yu, Yu-Ming Kang, and Qing-Feng Su
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Hydrothermal sysnthesis ,Luminescence ,Angina pectoris ,Endothelial cells ,Chemistry ,QD1-999 - Abstract
Via tuning the central metal ions from Zn(II) to Cd(II), two new coordination polymers was acquired in success, namely {(H3O)[Zn4(bptc)3(3-bpmh)]}n·6n(H2O) (1) and [Cd3(bptc)(3-bpmh)(H2O)3]n·4n(H2O) (2) (H3bptc = biphenyl-3,4′,5-tricarboxylic acid, 3-bpmh = N,N-bis-pyridin-3-ylmethylene-hydrazine), under hydrothermal conditions. The luminescent properties investigations showed that 1–2 emit intense luminescence with different maximum emission peaks. Their therapeutic and nursing protective effects on angina pectoris were assessed and we also discussed the corresponding mechanism simultaneously. The content of Interleukin-6 (IL-6) and soluble vascular cell adhesive molecule (SVCAM-1) released by endothelial cells (EC) was discovered through enzyme linked immunosorbent assay (ELISA) detection kit. Besides, the activation of Notch signaling pathway was also evaluated by the real time reverse transcription-polymerase chain reaction (RT-PCR). Influence of compounds on the peripheral blood white blood cell (WBC) numbers was measured with flow cytometry. We utilized optical coherence tomography (OCT) to measure the thickness of the fibrous cap of atherosclerotic plaque in patients with angina pectoris.
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- 2022
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5. Two new Cd(II)/Co(II) compounds: Luminescent and photocatalytic property, and treatment activity on coronary artery atherosclerosis
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Hai-Bo Yu, Feng-Jiang Chen, Jing Li, Yu-Ming Kang, Yan-Kun Zhang, and Yuan Shan
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Luminescence ,Photocatalysis ,Coronary artery atherosclerosis ,Chemistry ,QD1-999 - Abstract
Two new compounds, namely [Cd2(L)2(4-pybim)2(H2O)]n·3n(H2O) (1) and [Co(cam)(4-pybim)]n·n(H2O) (2) (H2L = succinic acid, H2cam = D-(+)-camphoric acid, 4-pybim = (4-pyridyl)benzimidazole), were successfully synthesized by the combination of carboxylate ligand, 4-pybim ligand and corresponding metal salts. Moreover, the luminescent property of 1 and photocatalytic activity of 2 were also investigated in detail. The application values of the new compounds against coronary artery atherosclerosis were evaluated and the detail mechanism was assessed simultaneously. First of all, the inflammatory cytokines levels released into plasma after compound treatment was measured with the detection of enzyme-linked immunosorbent assay. Then, the relative expression of the signaling pathway of NF-κb in the vascular endothelial cells was tested through exploiting the real time reverse transcription-polymerase.
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- 2022
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6. Correction: Lin et al. Study on the Development and Growth of Coral Larvae. Appl. Sci. 2022, 12, 5255
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Chiahsin Lin, Chia-Ming Kang, Chih-Yang Huang, Hsing-Hui Li, and Sujune Tsai
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n/a ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
There was an error in the original publication [...]
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- 2022
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7. Precise Sn-Doping Modulation for Optimizing CdWO4 Nanorod Photoluminescence
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K. Manjunatha, Ming-Kang Ho, Tsu-En Hsu, Hsin-Hao Chiu, Tai-Yue Li, B. Vijaya Kumar, P. Muralidhar Reddy, Ting San Chan, Yu-Hao Wu, Bi-Hsuan Lin, Artashes Karmenyan, Chia-Liang Cheng, Ashish Chhaganlal Gandhi, and Sheng Yun Wu
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Sn-doping ,photoluminescence ,CdWO4 rods ,Raman spectra ,synchrotron-based PXRD ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The cadmium tungstate rods have been given much attention due to their potential for usage in numerous luminescent applications. We have prepared single crystalline Sn-doped Cd1−xSnxWO4 (where x = 0, 1, 3, and 5%) nanorods (NRDs) and characterized them using refined X-ray diffraction and TEM analysis, revealing a monoclinic phase and a crystallite size that decreased from 62 to 38 nm as Sn concentration increased. Precise Sn doping modulation in CdWO4 NRDs causes surface recombination of electrons and holes, which causes the PL intensity to decrease as the Sn content rises. The chromaticity diagram shows that an increase in the Sn content caused a change in the emission color from sky blue to light green, which was attributed to the increased defect density. The photoluminescence time decay curve of all samples fit well with double-order exponential decay, and the average decay lifetime was found to be 1.11, 0.93, and 1.16 ns for Cd1−xSnxWO4, x = 0, 1, and 5%, respectively. This work provides an understanding of the behavior of Sn-doped CdWO4 NRDs during electron transitions and the physical nature of emission that could be used in bio-imaging, light sources, displays, and other applications.
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- 2022
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8. Innovation Glass-Ceramic Spray Deposition Technology Improving the Adhesive Performance for Zirconium-Based Dental Restorations
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Chien-Ming Kang, Dan-Jae Lin, Sheng-Wei Feng, Cheng-Yuan Hung, Shogo Iwaguro, and Tzu-Yu Peng
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zirconia ,lithium disilicate glass-ceramic ,spray deposition ,thermocycling ,shear bond strength ,dental restorations ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Glass-ceramic spray deposition (GCSD) is a novel technique for coating lithium disilicate (LD) glass-ceramics onto zirconia through simple tempering steps. GCSD has been proven to improve the bonding of zirconia to resin cement, but the effect of etching time on GCSD and the long-term durability of the bond achieved remain unknown. The effects of air abrasion with aluminum particles (ABB) and air abrasion (GAB) or etching with 5.0% hydrogen fluoride (HF) for 20, 60, 90, and 120 s (G20, G60, G90, and G120) on the resin cement–zirconia bond were studied. LD was included as a control (LDG). The microstructure, sub-micron roughness, wettability, and phase changes of samples were analyzed. After resin cement was bonded to zirconia, half of the samples were subjected to thermocycling (5000 cycles at 5–55 °C). The bond strengths of the samples were determined in shear bond strength (SBS) tests (n = 10 per group). An LD structure can be formed on zirconia after GCSD and proper etching processes, which result in high roughness and a hydrophilic nature. GCSD and HF etching significantly improved SBS, with G90 and G120 samples with pre- or post-thermocycling exhibiting SBS values comparable to those of LDG (p > 0.760). The surface characteristics of the LD layer are influenced by the etching time and affect the SBS of the bond of zirconia to resin cement. HF etching for 90–120 s after GCSD results in zirconia with SBS and bond durability comparable to LD.
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- 2022
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9. Formic Acid Generation from CO2 Reduction by MOF-253 Coordinated Transition Metal Complexes: A Computational Chemistry Perspective
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Meng-Chi Hsieh, Ranganathan Krishnan, and Ming-Kang Tsai
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metal-organic framework ,carbon dioxide reduction ,density functional theory ,transition metal catalysts ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
The inclusion of transition metal elements within metal–organic frameworks (MOFs) is considered one of the most promising approaches for enhancing the catalytic capability of MOFs. In this study, MOF-253 containing bipyridine coordination sites is investigated for possible transition metal chelation, and a consequent possible CO2 reduction mechanism in the formation of formic acid. All transition metal elements of the third, fourth and fifth periods except hafnium and the lanthanide series are considered using density functional theory calculations. Two distinct types of CO2 reduction mechanisms are identified: (1) the five-coordination Pd center, which promotes formic acid generation via an intramolecular proton transfer pathway; (2) several four-coordination metal centers, including Mn, Pd, and Pt, which generate formic acid by means of heterolytic hydrogen activation. The MOF-253 environment is found to promote beneficial steric hindrance, and to constrain metal–ligand orientation, which consequently facilitates the formation of formic acid, particularly with the tetrahedral Mn center at high-spin electronic state.
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- 2022
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10. Study on the Development and Growth of Coral Larvae
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Chiahsin Lin, Chia-Ming Kang, Chih-Yang Huang, Hsing-Hui Li, and Sujune Tsai
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coral ,larvae ,development ,polyp ,skeleton ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Studies on the early development of corals are required for academic research on coral reefs and applied reef conservation, but the interval between observations is usually weeks or months. Thus, no study has comprehensively explored the development of coral larvae after settlement. This study observed Galaxea fascicularis, Mycedium elephantotus, Pocillopora verrucosa, and Seriatopora caliendrum larvae after settlement, including their growth process and the formation of tentacles, skeletons, and polyps. The G. fascicularis and M. elephantotus polyps exhibited the skeleton-over-polyp mechanism, whereas the P. verrucosa and S. caliendrum polyps exhibited the polyp-over-skeleton mechanism. During asexual reproduction, the Symbiodiniaceae species clustered on the coenosarc, resulting in polyp development and skeletal growth. M. Elephantotus was unique in that its tentacles were umbrella-shaped, and its polyp growth and Symbiodiniaceae species performance during asexual reproduction differed from those of the other three corals. Although both P. verrucosa and S. caliendrum have branching morphologies, their vertical development stages were dissimilar. S. caliendrum relied on the mutual pushing of individuals in the colony to extend upward, whereas P. verrucosa had a center individual that developed vertically. The findings of this study can serve as a reference for future research on coral breeding, growth, and health assessments.
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- 2022
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11. Model-based learning about structures and properties of chemical elements and compounds via the use of augmented realities
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Chiu Mei-Hung, Chou Chin-Cheng, Chen Yi-Hung, Hung TaMin, Tang Wei-Tian, Hsu Jin-Wei, Liaw Hongming Leonard, and Tsai Ming-Kang
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chemistry education ,modeling-based learning ,augmented reality ,virtual reality ,technology ,Chemistry ,QD1-999 - Abstract
Scientific models play a vital role in science learning, representing major characteristics of scientific phenomena. A useful visualization of models that matches target concepts to source objects can facilitate students’ learning of abstract and complex structures of chemical elements and compounds. This report will show the importance of visualization and innovative technology (such as augmented reality), which has the potential of supporting students’ learning of stereochemistry and interactions among molecules. Examples (including organic compounds, chemical elements of 1A and 7A in the periodic table, water polarity, and carbon nanotube) are drawn to illustrate the potential use of augmented reality in chemistry instruction.
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- 2018
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12. Identification of traits and genes associated with lodging resistance in maize
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Ding-ming Kang, Wen-Xue Li, Pengshuai Yan, Yumei Hu, Hongqiu Wang, Yafei Wang, Huan Chen, Yu Guo, Qingguo Du, and Zhonghua Wang
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0106 biological sciences ,0301 basic medicine ,Agriculture (General) ,Phloroglucinol ,Plant Science ,Biology ,01 natural sciences ,Lignin ,S1-972 ,Transcriptome ,Cell wall ,03 medical and health sciences ,chemistry.chemical_compound ,Inbred strain ,Lodging ,Gene ,Vascular tissue ,Agriculture ,Cortex (botany) ,Maize ,Horticulture ,030104 developmental biology ,Sclerenchyma cell ,chemistry ,Differentially expressed genes ,Agronomy and Crop Science ,010606 plant biology & botany - Abstract
Lodging is a major problem limiting maize yield worldwide. However, the mechanisms of lodging resistance remain incompletely understood for maize. Here, we evaluated 443 maize accessions for lodging resistance in the field. Five lodging-resistant accessions and five lodging-sensitive accessions were selected for further research. The leaf number, plant height, stem diameter, and rind penetrometer resistance were similar between lodging-resistant and -sensitive inbred lines. The average thickness of sclerenchymatous hypodermis layer was thicker and the vascular area was larger in the lodging-resistant lines compared with lodging-sensitive lines. Although total lignin content in stem tissue did not significantly differ between lodging-resistant and -sensitive lines, phloroglucinol staining revealed that the lignin content of the cell wall in the stem cortex and in the stem vascular tissue near the cortex was higher in the lodging-resistant lines than in the lodging-sensitive lines. Analysis of strand-specific RNA-seq transcriptome showed that a total of 793 genes were up-regulated and 713 genes were down-regulated in lodging-resistant lines relative to lodging-sensitive lines. The up-regulated genes in lodging-resistant lines were enriched in cell wall biogenesis. These results indicated that modification of cell wall biosynthesis would contribute to lodging resistance of maize.
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- 2021
13. Astaxanthin Ameliorates Blood Pressure in Salt-Induced Prehypertensive Rats Through ROS/MAPK/NF-κB Pathways in the Hypothalamic Paraventricular Nucleus
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Xiao-Jing Yu, Yi-Ming Lei, Hong-Li Gao, Chen-Long Wang, Yu-Ming Kang, Yan Zhang, Jia-Yue Yu, Kai-Li Liu, Nian-Ping Zhang, Ying Li, Dong-Miao Zong, Dong-Dong Zhang, and Hua Tian
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Male ,MAPK/ERK pathway ,medicine.medical_specialty ,Anti-Inflammatory Agents ,Xanthophylls ,Toxicology ,medicine.disease_cause ,Antioxidants ,Superoxide dismutase ,Prehypertension ,Internal medicine ,medicine ,Animals ,Arterial Pressure ,Phosphorylation ,Sodium Chloride, Dietary ,Interleukin 6 ,Molecular Biology ,Antihypertensive Agents ,chemistry.chemical_classification ,Reactive oxygen species ,Rats, Inbred Dahl ,biology ,Tyrosine hydroxylase ,Kinase ,NF-kappa B ,Disease Models, Animal ,Oxidative Stress ,Endocrinology ,chemistry ,Catalase ,biology.protein ,Mitogen-Activated Protein Kinases ,Reactive Oxygen Species ,Cardiology and Cardiovascular Medicine ,Oxidative stress ,Paraventricular Hypothalamic Nucleus ,Signal Transduction - Abstract
Astaxanthin (AST) has a variety of biochemical effects, including anti-inflammatory, antioxidative, and antihypertensive functions. The aim of the present study was to determine whether AST ameliorates blood pressure in salt-induced prehypertensive rats by ROS/MAPK/NF-κB pathways in hypothalamic paraventricular nucleus. To explore the central effects of AST on the development of blood pressure, prehypertensive rats were induced by a high-salt diet (HS, 8% NaCl) and its control groups were treated with normal-salt diet (NS, 0.3% NaCl). The Dahl salt-sensitive (S) rats with HS diet for 6 weeks received AST or vehicle by gastric perfusion for 6 weeks. Compared to those with NS diet, rats with HS diet exhibited increased mean arterial pressure (MAP) and heart rate (HR). These increases were associated with higher plasma level of norepinephrine (NE), interleukin 1β (IL-1β), and interleukin 6 (IL-6); elevated PVN level of reactive oxygen species (ROS), NOX2, and NOX4, that of IL-1β, IL-6, monocyte chemotactic protein 1 (MCP-1), tyrosine hydroxylase (TH), phosphorylation extracellular-signal-regulated kinase (p-ERK1/2), phosphorylation Jun N-terminal kinases (p-JNK), nuclear factor-kappa B (NF-κB) activity; and lower levels of IL-10, superoxide dismutase (SOD), and catalase (CAT) in the PVN. In addition, our data demonstrated that chronic AST treatment ameliorated these changes in the HS but not NS diet rats. These data suggested that AST could alleviate prehypertensive response in HS-induced prehypertension through ROS/MAPK/NF-κB pathways in the PVN.
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- 2021
14. A Singlet Oxygen Reservoir Based on Poly-Pyridone and Porphyrin Nanoscale Metal–Organic Framework for Cancer Therapy
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Xian-Zheng Zhang, Ming-Kang Zhang, Bo-Ru Xie, Xuan Zeng, Chu-Xin Li, Yun Yu, Xiao-Shuang Wang, and Jin-Yue Zeng
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Singlet oxygen ,medicine.medical_treatment ,Cancer therapy ,Photodynamic therapy ,General Chemistry ,Photochemistry ,Porphyrin ,chemistry.chemical_compound ,chemistry ,Polymerization ,medicine ,Metal-organic framework ,Nanoscopic scale ,Derivative (chemistry) - Abstract
Here, a methacrylate-modified pyridone derivative (mPYR) was loaded into a porphyrin nanoscale metal–organic framework (porphyrin-nMOF). Then, the loaded mPYR was further polymerized to obtain poly...
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- 2021
15. Chronic Blockade of NMDAR Subunit 2A in the Hypothalamic Paraventricular Nucleus Alleviates Hypertension Through Suppression of MEK/ERK/CREB Pathway
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Hong-Li Chi, Tong Xiao, Xiao-Jing Yu, Hong-Li Gao, Abdoulaye Issotina Zibrila, Yu-Ming Kang, Hong-Bao Li, Ying Li, Jie Qi, Yan Zhang, Xiao-Lian Shi, Li-Yan Fu, Yu-Xin Lu, Qing Su, and Yan-Mei Chen
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MAPK/ERK pathway ,medicine.medical_specialty ,MAP Kinase Signaling System ,CREB ,Receptors, N-Methyl-D-Aspartate ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,Internal Medicine ,medicine ,Animals ,Cyclic AMP Response Element-Binding Protein ,Protein kinase A ,Protein kinase B ,PI3K/AKT/mTOR pathway ,030304 developmental biology ,PEAQX ,0303 health sciences ,biology ,business.industry ,Kinase ,Rats ,Endocrinology ,chemistry ,Hypertension ,biology.protein ,Phosphorylation ,business ,030217 neurology & neurosurgery ,Paraventricular Hypothalamic Nucleus - Abstract
BACKGROUND N-Methyl-d-aspartate receptor (NMDAR) in the hypothalamic paraventricular nucleus (PVN) plays critical roles in regulating sympathetic outflow. Studies showed that acute application of the antagonists of NMDAR or its subunits would reduce sympathetic nerve discharges. However, little is known about the effect of long-term management of NMDAR in hypertensive animals. METHODS PEAQX, the specific antagonist of NMDAR subunit 2A (GluN2A) was injected into both sides of the PVN of two-kidney, one-clip (2K1C) renal hypertensive rats and control (normotensive rats) for 3 weeks. RESULTS Three weeks of PEAQX infusion significantly reduced the blood pressure of the 2K1C rats. It managed to resume the balance between excitatory and inhibitory neural transmitters, reduce the level of proinflammatory cytokines and reactive oxygen species in the PVN, and reduce the level of norepinephrine in plasma of the 2K1C rats. PEAQX administration also largely reduced the transcription and translation levels of GluN2A and changed the expression levels of NMDAR subunits 1 and 2B (GluN1 and GluN2B). In addition, NMDAR was known to function through activating the extracellular regulated protein kinases (ERK) or phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways. In our study, we found that in the PVN of 2K1C rats treated with PEAQX, the phosphorylation levels of mitogen-activated protein kinase kinase (MEK), ERK1/2, and cAMP-response element-binding protein (CREB) significantly reduced, while the phosphorylation level of PI3K did not change significantly. CONCLUSIONS Chronic blockade of GluN2A alleviates hypertension through suppression of MEK/ERK/CREB pathway.
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- 2021
16. Bottlebrush Polymers Carrying Side Chains on Every Backbone Atom: Controlled Synthesis, Polymerization-Induced Emission, and Circularly Polarized Luminescence
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Li Zhou, Xun-Hui Xu, Shu-Ming Kang, Na Liu, Xue Song, Wen-Bin Liu, and Zong-Quan Wu
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Organic Chemistry ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,Grafting ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry ,Polymerization ,Atom ,Materials Chemistry ,Side chain ,0210 nano-technology ,Luminescence - Abstract
Controlled synthesis of bottlebrush polymers with high grafting density and carrying polymeric side chains on every backbone atom remains a great challenge. In this work, a series of well-defined p...
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- 2021
17. Inhibition of miR-135a-5p attenuates vascular smooth muscle cell proliferation and vascular remodeling in hypertensive rats
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Ying Tong, Qi Chen, Jue-Jin Wang, Guo-Qing Zhu, Chao Ye, Yuehua Li, Fen Zheng, Jing-Yu Chen, Ai-Dong Chen, Jianzhen Lei, Hong Zhou, Yu-Ming Kang, Nan Wu, and Guo-Wei Wan
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Male ,0301 basic medicine ,medicine.medical_specialty ,Myofilament ,Vascular smooth muscle ,Myocytes, Smooth Muscle ,Vascular Remodeling ,Rats, Inbred WKY ,Muscle, Smooth, Vascular ,Article ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Rats, Inbred SHR ,Internal medicine ,medicine ,Animals ,Gene silencing ,Pharmacology (medical) ,cardiovascular diseases ,Cells, Cultured ,Cell Proliferation ,Pharmacology ,Gene knockdown ,biology ,Chemistry ,Cell growth ,General Medicine ,musculoskeletal system ,FNDC5 ,Rats ,Fibronectin ,MicroRNAs ,030104 developmental biology ,Endocrinology ,030220 oncology & carcinogenesis ,Hypertension ,cardiovascular system ,biology.protein - Abstract
Proliferation of vascular smooth muscle cells (VSMCs) greatly contributes to vascular remodeling in hypertension. This study is to determine the roles and mechanisms of miR-135a-5p intervention in attenuating VSMC proliferation and vascular remodeling in spontaneously hypertensive rats (SHRs). MiR-135a-5p level was raised, while fibronectin type III domain-containing 5 (FNDC5) mRNA and protein expressions were reduced in VSMCs of SHRs compared with those of Wistar–Kyoto rats (WKYs). Enhanced VSMC proliferation in SHRs was inhibited by miR-135a-5p knockdown or miR-135a-5p inhibitor, but exacerbated by miR-135a-5p mimic. VSMCs of SHRs showed reduced myofilaments, increased or even damaged mitochondria, increased and dilated endoplasmic reticulum, which were attenuated by miR-135a-5p inhibitor. Dual-luciferase reporter assay shows that FNDC5 was a target gene of miR-135a-5p. Knockdown or inhibition of miR-135a-5p prevented the FNDC5 downregulation in VSMCs of SHRs, while miR-135a-5p mimic inhibited FNDC5 expressions in VSMCs of both WKYs and SHRs. FNDC5 knockdown had no significant effects on VSMC proliferation of WKYs, but aggravated VSMC proliferation of SHRs. Exogenous FNDC5 or FNDC5 overexpression attenuated VSMC proliferation of SHRs, and prevented miR-135a-5p mimic-induced enhancement of VSMC proliferation of SHR. MiR-135a-5p knockdown in SHRs attenuated hypertension, normalized FNDC5 expressions and inhibited vascular smooth muscle proliferation, and alleviated vascular remodeling. These results indicate that miR-135a-5p promotes while FNDC5 inhibits VSMC proliferation in SHRs. Silencing of miR-135a-5p attenuates VSMC proliferation and vascular remodeling in SHRs via disinhibition of FNDC5 transcription. Either inhibition of miR-135a-5p or upregulation of FNDC5 may be a therapeutically strategy in attenuating vascular remodeling and hypertension.
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- 2021
18. Chronic Infusion of Astaxanthin Into Hypothalamic Paraventricular Nucleus Modulates Cytokines and Attenuates the Renin–Angiotensin System in Spontaneously Hypertensive Rats
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Qiu-Yue Yi, Yu-Ming Kang, Ying Li, Kai-Li Liu, Hua Tian, Hong-Li Gao, Jin-Jun Liu, Yi-Yi Zuo, Guo-Qing Zhu, Dong-Dong Zhang, Li-Yan Fu, Xiao-Min Wang, Kai B Kang, Xiao-Lian Shi, Jia-Yue Yu, Jie Qi, Xiao-Jing Yu, and Yan-Mei Chen
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Male ,0301 basic medicine ,medicine.medical_specialty ,Time Factors ,Anti-Inflammatory Agents ,Inflammation ,Xanthophylls ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Rats, Inbred WKY ,Proinflammatory cytokine ,Renin-Angiotensin System ,Pathogenesis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Astaxanthin ,Rats, Inbred SHR ,Internal medicine ,Renin–angiotensin system ,medicine ,Animals ,Arterial Pressure ,Infusions, Parenteral ,Receptor ,Antihypertensive Agents ,Pharmacology ,chemistry.chemical_classification ,Reactive oxygen species ,Chemistry ,Disease Models, Animal ,030104 developmental biology ,Endocrinology ,Hypertension ,Cytokines ,Inflammation Mediators ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,hormones, hormone substitutes, and hormone antagonists ,Oxidative stress ,Paraventricular Hypothalamic Nucleus - Abstract
Oxidative stress, the renin-angiotensin system (RAS), and inflammation are some of the mechanisms involved in the pathogenesis of hypertension. The aim of this study is to examine the protective effect of the chronic administration of astaxanthin, which is extracted from the shell of crabs and shrimps, into hypothalamic paraventricular nucleus (PVN) in spontaneously hypertensive rats. Animals were randomly assigned to 2 groups and treated with bilateral PVN infusion of astaxanthin or vehicle (artificial cerebrospinal fluid) through osmotic minipumps (Alzet Osmotic Pumps, Model 2004, 0.25 μL/h) for 4 weeks. Spontaneously hypertensive rats had higher mean arterial pressure and plasma level of norepinephrine and proinflammatory cytokine; higher PVN levels of reactive oxygen species, NOX2, NOX4, IL-1β, IL-6, ACE, and AT1-R; and lower PVN levels of IL-10 and Cu/Zn SOD, Mn SOD, ACE2, and Mas receptors than Wistar-Kyoto rats. Our data showed that chronic administration of astaxanthin into PVN attenuated the overexpression of reactive oxygen species, NOX2, NOX4, inflammatory cytokines, and components of RAS within the PVN and suppressed hypertension. The present results revealed that astaxanthin played a role in the brain. Our findings demonstrated that astaxanthin had protective effect on hypertension by improving the balance between inflammatory cytokines and components of RAS.
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- 2021
19. Highly Regioselective and Helix-Sense Selective Living Polymerization of Phenyl and Alkoxyallene Using Chiral Nickel(II) Catalysts
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Xun-Hui Xu, Shu-Ming Kang, Li Zhou, Na Liu, Chonglong Li, Run-Tan Gao, Zong-Quan Wu, and Lei Xu
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inorganic chemicals ,chemistry.chemical_classification ,Circular dichroism ,Polymers and Plastics ,Double bond ,Chemistry ,organic chemicals ,Allene ,Organic Chemistry ,technology, industry, and agriculture ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Monomer ,Polymerization ,Polymer chemistry ,Materials Chemistry ,Living polymerization ,0210 nano-technology ,Chirality (chemistry) - Abstract
Facile synthesis of high optically active helical polymers from achiral monomers still remains a great challenge. In this work, two chiral Ni(II) catalysts bearing chiral R- or S-2a ligands were facilely prepared which can efficiently initiate the living/controlled polymerization of allene monomers and afford well-defined polyallenes in high yields with controlled molecular masses (Mₙs) and low molecular mass distributions (Mw/Mₙs). The catalysts showed interesting regioselectivity on the cumulated double bonds of allene monomers, as the polymerizations were highly selective which occurred on 2,3-double bonds. Moreover, the polymerization of achiral allene monomers using chiral Ni(II) catalysts showed remarkable helix-sense selectivity. The yielded polyallenes exhibited high optical activity due to the formation of a predominant one-handed helix as revealed by circular dichroism, UV–vis, and direct atomic force microscopy (AFM) observations as well. The predominant one-handed helicity of the generated polyallenes was solely determined by the chirality of the Ni(II) catalysts.
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- 2021
20. Highly 2,3-selective and fast living polymerization of alkyl-, alkoxy- and phenylallenes using nickel(<scp>ii</scp>) catalysts
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Zong-Quan Wu, Li Zhou, Shu-Ming Kang, Xun-Hui Xu, Lei Xu, and Na Liu
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chemistry.chemical_classification ,Polymers and Plastics ,Allene ,Organic Chemistry ,Regioselectivity ,Bioengineering ,Biochemistry ,chemistry.chemical_compound ,chemistry ,Polymerization ,Polymer chemistry ,Alkoxy group ,Moiety ,Living polymerization ,Molar mass distribution ,Alkyl - Abstract
Polyallene is one of the most attractive synthetic precursors for constructing functional materials due to its unsaturated bonds on the main chain or pendants. The facile synthesis of high regioselectivity polyallenes still remains a challenge. In this work, a novel Ni(II) catalyst with a phosphine bearing sulfoxide moiety named Ming-Phos (L4) as a ligand was developed to initiate the polymerization of various allene monomers efficiently in a fast and living/controlled manner. The well-defined polyallenes were afforded in high yields with a controlled molar mass (Mn) and low molar mass distribution (Mw/Mn). Moreover, the Ni(II)/L4 catalyst exhibited fascinating regioselectivity on the accumulated double bonds of allene monomers, and the 2,3-regioselectivity of the polymerization of allene monomers was up to >99.9%. Remarkably, various monomers with different functional groups inculding alkyl, alkoxy and substituted phenyl groups could be polymerized effectively using Ni(II)/L4 as the initiator, affording polyallenes with higher 2,3-regioselectivity. The regioselectivity, and thermodynamic and crystallization properties of the polyallenes were confirmed by 1H NMR, DSC, TGA and WAXD, respectively.
- Published
- 2021
21. Carbon emission flux and storage in the degraded peatlands of the Zoige alpine area in the Qinghai–Tibetan Plateau
- Author
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Lijuan Cui, Wei Li, Wenchang Zhou, Yifei Wang, and Xiao-Ming Kang
- Subjects
Qinghai tibetan plateau ,Peat ,Emission flux ,chemistry ,Water table ,Soil Science ,chemistry.chemical_element ,Environmental science ,Atmospheric sciences ,Pollution ,Agronomy and Crop Science ,Carbon - Published
- 2020
22. FNDC5 Attenuates Oxidative Stress and NLRP3 Inflammasome Activation in Vascular Smooth Muscle Cells via Activating the AMPK-SIRT1 Signal Pathway
- Author
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Guo-Qing Zhu, Bing Zhou, Yun Qiu, Yuehua Li, Hong Zhou, Nan Wu, Qi Chen, Ai-Dong Chen, and Yu-Ming Kang
- Subjects
Male ,0301 basic medicine ,Aging ,Vascular smooth muscle ,Inflammasomes ,medicine.disease_cause ,Biochemistry ,Mice ,0302 clinical medicine ,AMP-Activated Protein Kinase Kinases ,Sirtuin 1 ,Aorta ,Mice, Knockout ,NADPH oxidase ,biology ,Chemistry ,Angiotensin II ,General Medicine ,Cell biology ,030220 oncology & carcinogenesis ,Hypertension ,cardiovascular system ,medicine.symptom ,hormones, hormone substitutes, and hormone antagonists ,Signal Transduction ,Research Article ,Article Subject ,Myocytes, Smooth Muscle ,Phosphorylation Inhibition ,Inflammation ,Cell Line ,03 medical and health sciences ,Downregulation and upregulation ,NLR Family, Pyrin Domain-Containing 3 Protein ,medicine ,Animals ,Humans ,QH573-671 ,AMPK ,Cell Biology ,Fibronectins ,Rats ,Mice, Inbred C57BL ,Disease Models, Animal ,Oxidative Stress ,030104 developmental biology ,biology.protein ,Cytology ,Protein Kinases ,Oxidative stress - Abstract
Vascular oxidative stress and inflammation play a major role in vascular diseases. This study was aimed at determining the protective roles of fibronectin type III domain-containing 5 (FNDC5) in angiotensin II- (Ang II-) induced vascular oxidative stress and inflammation and underlying mechanisms. Wild-type (WT) and FNDC5-/- mice, primary mouse vascular smooth muscle cells (VSMCs), and the rat aortic smooth muscle cell line (A7R5) were used in the present study. Subcutaneous infusion of Ang II caused more serious hypertension, vascular remodeling, oxidative stress, NLRP3 inflammasome activation, AMPK phosphorylation inhibition, and SIRT1 downregulation in the aorta of FNDC5-/- mice than those of WT mice. Exogenous FNDC5 attenuated Ang II-induced superoxide generation, NADPH oxidase 2 (NOX2) and NLRP3 upregulation, mature caspase-1, and interleukin-1β (IL-1β) production in A7R5 cells. The protective roles of FNDC5 were prevented by SIRT-1 inhibitor EX527, AMPK inhibitor compound C, or integrin receptor inhibitor GLPG0187. FNDC5 attenuated the Ang II-induced inhibition in SIRT1 activity, SIRT1 protein expression, and AMPKα phosphorylation in A7R5 cells, which were prevented by compound C, EX527, and GLPG0187. FNDC5 deficiency deteriorated Ang II-induced oxidative stress, NLRP3 inflammasome activation, AMPK phosphorylation inhibition, and SIRT1 downregulation in primary aortic VSMCs of mice, which were prevented by exogenous FNDC5. These results indicate that FNDC5 deficiency aggravates while exogenous FNDC5 alleviates the Ang II-induced vascular oxidative stress and NLRP3 inflammasome activation via the AMPK-SIRT1 signal pathway in VSMCs.
- Published
- 2020
23. Distinct functions and prognostic values of RORs in gastric cancer
- Author
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Feng Gu, Yuming Liu, Shujie Cheng, Ming Kang, Yan Liu, Jihong Yang, Wendu Duan, and Yuan Liu
- Subjects
0301 basic medicine ,Mrna expression ,proliferation ,Retinoic acid ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Medicine ,Lauren classification ,In patient ,Receptor ,Gene knockdown ,business.industry ,gastric cancer ,Wnt signaling pathway ,Cancer ,General Medicine ,medicine.disease ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,retinoic acid receptor-related orphan receptors ,Cancer research ,prognosis ,business ,Research Article - Abstract
Retinoic acid receptor-related orphan receptors (RORs) are frequently abnormally expressed in several human malignancies, including gastric cancer (GC). RORs are involved in the development and progression of GC through Wnt signaling pathway receptors and other common receptors. However, the prognostic roles of individual RORs in patients with GC remain elusive. We accessed the prognostic roles of three RORs (RORα, RORβ, and RORγ) through “The Kaplan–Meier plotter” (KM plotter) database in patients with GC. For all patients with GC who were followed for 20 years, the low mRNA expression of all three RORs showed a significant correlation with better outcomes. We further accessed the prognostic value of individual RORs in different clinical pathological features including Lauren classification, clinical stages, pathological grades, HER2 status, and different treatments methods. The RORs demonstrated critical prognostic roles in GC. Expressions of RORs were higher in GC tissues when compared with normal gastric tissues. Moreover, knockdown of RORs significantly inhibited cell proliferation and migration, suggesting an oncogenic role of RORs in human GC. These findings suggest potential roles of RORs as biomarkers for GC prognosis and as oncogenes in GC.
- Published
- 2020
24. Revisiting Silica Networks by Small-angle Neutron Scattering and Synchrotron Radiation X-ray Imaging Techniques
- Author
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Ming Kang, Xin-Wei Kang, Ying-Ze Song, Lixian Song, Qing-Xi Yuan, Dong Liu, Feng Chen, Ping Zhang, and Xiuli Zhao
- Subjects
Filler (packaging) ,Materials science ,Polymers and Plastics ,General Chemical Engineering ,Organic Chemistry ,X-ray ,Synchrotron radiation ,Neutron scattering ,Silicone rubber ,Small-angle neutron scattering ,Matrix (geology) ,Amorphous solid ,chemistry.chemical_compound ,chemistry ,Composite material - Abstract
The silicone rubber composites present remarkable mechanical properties due to the double network structure constructed with molecular network of matrix and filler network of silica. Nevertheless, the filler network structure and corresponding reinforcement mechanism are still under debate and need to be further probed with the aid of applicative advanced analysis techniques. Herein, small-angle neutron scattering (SANS) and synchrotron radiation X-ray nano-computed tomography (Nano-CT) techniques are employed to explore the evolution of filler networks of fumed, precipitated and sol-gel silica, respectively. Our studying results reveal the formation of filler network constructed by the interconnecting of branched silica aggregates. And the silica with highly associated structure, pertaining to amorphous morphology, small size, and large surface area, presents short distance and effective molecular chain bridge between aggregates, thus forming strong and steady filler networks. This work would provide deep-seated revisiting of filler networks and corresponding reinforcement mechanism and offer guidance for optimizing the mechanical properties of silicone rubber.
- Published
- 2020
25. PSb+P Ligand: Platform for a Stibenium to Transition-Metal Interaction
- Author
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Nagarjuna Kumar Srungavruksham, Ming Kang Tsai, Ching-Wen Chiu, and Yi-Hung Liu
- Subjects
chemistry.chemical_classification ,010405 organic chemistry ,Ligand ,Cationic polymerization ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Divalent ,Coordination complex ,Inorganic Chemistry ,chemistry ,Transition metal ,Polymer chemistry ,Physical and Theoretical Chemistry ,Pnictogen - Abstract
The coordination chemistry of cationic divalent pnictogen ligands, such as nitrenium and phosphenium, has been well-explored in recent years. However, corresponding studies of a heavier congener, s...
- Published
- 2020
26. Alternative Pathway to the Formation of trans-Cinnamic Acid Derived from <scp>l</scp>-Phenylalanine in Tea (Camellia sinensis) Plants and Other Plants
- Author
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Ziyin Yang, Ping Xu, Haibo Tan, Lanting Zeng, Fang Dong, Ming Kang, Yinyin Liao, and Xiaoqin Wang
- Subjects
0106 biological sciences ,Phenylpropanoid ,biology ,fungi ,010401 analytical chemistry ,Phenylpyruvic acid ,food and beverages ,Phenylalanine ,General Chemistry ,biology.organism_classification ,01 natural sciences ,Cinnamic acid ,Lycopersicon ,0104 chemical sciences ,chemistry.chemical_compound ,Biosynthesis ,chemistry ,Botany ,Arabidopsis thaliana ,Camellia sinensis ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
trans-Cinnamic acid (CA) is a precursor of many phenylpropanoid compounds, including catechins and aroma compounds, in tea (Camellia sinensis) leaves and is derived from l-phenylalanine (l-Phe) deamination. We have discovered an alternative CA formation pathway from l-Phe via phenylpyruvic acid (PPA) and phenyllactic acid (PAA) in tea leaves through stable isotope-labeled precursor tracing and enzyme reaction evidence. Both PPA reductase genes (CsPPARs) involved in the PPA-to-PAA pathway were isolated from tea leaves and functionally characterized in vitro and in vivo. CsPPAR1 and CsPPAR2 transformed PPA into PAA and were both localized in the leaf cell cytoplasm. Rosa hybrida flowers (economic crop flower), Lycopersicon esculentum Mill. fruits (economic crop fruit), and Arabidopsis thaliana leaves (leaf model plant) also contained this alternative CA formation pathway, suggesting that it occurred in most plants, regardless of different tissues and species. These results improve our understanding of CA biosynthesis in tea plants and other plants.
- Published
- 2020
27. Epigenetic Effects Mediated by Antiepileptic Drugs and their Potential Application
- Author
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Chun-Lai Ma, Ming-Kang Zhong, and Fan-Cheng Kong
- Subjects
Epigenomics ,0301 basic medicine ,RNA, Untranslated ,Bioinformatics ,Epigenesis, Genetic ,Histones ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Untranslated RNA ,Neoplasms ,Gene expression ,Humans ,histone modification ,Pharmacology (medical) ,Epigenetics ,Pharmacology ,DNA methylation ,biology ,Translational medicine ,General Medicine ,Current Neuropharmacology ,Psychiatry and Mental health ,030104 developmental biology ,Histone ,Neurology ,chemistry ,Cardiovascular Diseases ,Molecular mechanism ,biology.protein ,Anticonvulsants ,Kidney Diseases ,Neurology (clinical) ,molecular mechanism ,Nervous System Diseases ,untranslated RNA ,application ,Protein Processing, Post-Translational ,Antiepileptic drug ,030217 neurology & neurosurgery ,DNA - Abstract
An epigenetic effect mainly refers to a heritable modulation in gene expression in the short term but does not involve alterations in the DNA itself. Epigenetic molecular mechanisms include DNA methylation, histone modification, and untranslated RNA regulation. Antiepileptic drugs have drawn attention to biological and translational medicine because their impact on epigenetic mechanisms will lead to the identification of novel biomarkers and possible therapeutic strategies for the prevention and treatment of various diseases ranging from neuropsychological disorders to cancers and other chronic conditions. However, these transcriptional and posttranscriptional alterations can also result in adverse reactions and toxicity in vitro and in vivo. Hence, in this review, we focus on recent findings showing epigenetic processes mediated by antiepileptic drugs to elucidate their application in medical experiments and shed light on epigenetic research for medicinal purposes.
- Published
- 2020
28. Synthesis and Infrared Multi‐band Absorption Properties of Core‐shell NaYF 4 :Yb 3+ , Er 3+ @SiO 2 Nanoparticles
- Author
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Rong Sun, Xiangmeng Lv, Lu Yuan, Simin Shen, Guanjun Chang, and Ming Kang
- Subjects
Inorganic Chemistry ,Core shell ,Multi band ,Chemistry ,Infrared ,Sio2 nanoparticles ,Analytical chemistry ,Absorption (electromagnetic radiation) ,Nanomaterials - Published
- 2019
29. Inhibition of Hypothalamic Inhibitor κB Kinase β/Nuclear Transcription Factor κB Pathway Attenuates Metabolism and Cardiac Dysfunction in Type 2 Diabetic Rats
- Author
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Ying Li, Kai-Li Liu, Tian-Ze Sun, Guo-Qing Zhu, Yu-Ming Kang, Hong-Bao Li, Xiao-Jing Yu, Xiao-Lian Shi, Hong-Li Gao, Yan-Mei Chen, and Jie Qi
- Subjects
Blood Glucose ,Male ,Cardiac function curve ,medicine.medical_specialty ,Diabetic Cardiomyopathies ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Inflammation ,Thiophenes ,medicine.disease_cause ,030218 nuclear medicine & medical imaging ,Proinflammatory cytokine ,Rats, Sprague-Dawley ,Pathogenesis ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Endocrinology ,Internal medicine ,medicine ,Hyperinsulinemia ,Animals ,Protein Kinase Inhibitors ,chemistry.chemical_classification ,Reactive oxygen species ,Arc (protein) ,Endocrine and Autonomic Systems ,business.industry ,Arcuate Nucleus of Hypothalamus ,NF-kappa B ,medicine.disease ,I-kappa B Kinase ,Rats ,Disease Models, Animal ,Diabetes Mellitus, Type 2 ,chemistry ,Echocardiography ,Cytokines ,medicine.symptom ,business ,Oxidative stress ,Signal Transduction - Abstract
Background: Inflammation and oxidative stress play important roles in energy imbalance and its complications. Recent research indicates that hypothalamic inflammation may contribute to the pathogenesis of metabolic syndrome and cardiac dysfunction, but the mechanisms remain unclear. We hypothesized that suppression of the proinflammatory IKKβ/NF-κB pathway in the hypothalamus can improve energy balance and cardiac function in type 2 diabetic (T2D) rats. Methods: Normal and T2D rats received bilateral hypothalamic arcuate nucleus (ARC) infusions of the IKKβ inhibitor SC-514 or vehicle via osmotic minipump. Metabolic phenotyping, immunohistochemical analyses, and biochemical analyses were used to investigate the outcomes of inhibition of the hypothalamic IKKβ. Echocardiography and glucometer were used for measuring cardiac function and blood glucose, respectively. Blood samples were collected for the evaluation of circulating proinflammatory cytokines. Heart was harvested for cardiac morphology evaluations. The ARC was harvested and analyzed for IKKβ, NF-κB, proinflammatory cytokines, reactive oxygen species (ROS), and NAD(P)H (gp91phox, p47phox) oxidase activity levels and neuropeptides. Results: Compared with normal rats, T2D rats were characterized by hyperglycemia, hyperinsulinemia, glucose intolerance, cardiac dysfunction, as well as higher ARC levels of IKKβ, NF-κB, proinflammatory cytokines, ROS, gp91phox, and p47phox. ARC infusion of the IKKβ inhibitor SC-514 attenuated all these changes in T2D rats, but not in normal rats. Conclusions: Our results indicate that the hypothalamic IKKβ/NF-κB pathway plays a key role in modulating energy imbalance and cardiac dysfunction, suggesting its potential therapeutic role during type 2 diabetes mellitus.
- Published
- 2019
30. Bilateral Paraventricular Nucleus Upregulation of Extracellular Superoxide Dismutase Decreases Blood Pressure by Regulation of the NLRP3 and Neurotransmitters in Salt-Induced Hypertensive Rats
- Author
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Hong-Bao Li, Juan Bai, Ying Li, Yan Zhang, Guo-Qing Zhu, Qing Su, Nian-Ping Zhang, Kai-Li Liu, Yu-Ming Kang, Xiao-Min Wang, Xiao-Jing Yu, and Jie Qi
- Subjects
chemistry.chemical_classification ,Pharmacology ,medicine.medical_specialty ,Chemistry ,Salt (chemistry) ,salt-induced hypertension ,RM1-950 ,neurotransmitters ,medicine.anatomical_structure ,Blood pressure ,Endocrinology ,nervous system ,Extracellular superoxide dismutase ,Downregulation and upregulation ,NLRP3 ,Internal medicine ,medicine ,Pharmacology (medical) ,Therapeutics. Pharmacology ,paraventricular nucleus ,Ec-SOD ,Nucleus ,Original Research - Abstract
Aims: Long-term salt diet induces the oxidative stress in the paraventricular nucleus (PVN) and increases the blood pressure. Extracellular superoxide dismutase (Ec-SOD) is a unique antioxidant enzyme that exists in extracellular space and plays an essential role in scavenging excessive reactive oxygen species (ROS). However, the underlying mechanism of Ec-SOD in the PVN remains unclear.Methods: Sprague–Dawley rats (150–200 g) were fed either a high salt diet (8% NaCl, HS) or normal salt diet (0.9% NaCl, NS) for 6 weeks. Each group of rats was administered with bilateral PVN microinjection of AAV-Ec-SOD (Ec-SOD overexpression) or AAV-Ctrl for the next 6 weeks.Results: High salt intake not only increased mean arterial blood pressure (MAP) and the plasma noradrenaline (NE) but also elevated the NAD(P)H oxidase activity, the NAD(P)H oxidase components (NOX2 and NOX4) expression, and ROS production in the PVN. Meanwhile, the NOD-like receptor protein 3 (NLRP3)–dependent inflammatory proteins (ASC, pro-cas-1, IL-β, CXCR, CCL2) expression and the tyrosine hydroxylase (TH) expression in the PVN with high salt diet were higher, but the GSH level, Ec-SOD activity, GAD67 expression, and GABA level were lower than the NS group. Bilateral PVN microinjection of AAV-Ec-SOD decreased MAP and the plasma NE, reduced NAD(P)H oxidase activity, the NOX2 and NOX4 expression, and ROS production, attenuated NLRP3-dependent inflammatory expression and TH, but increased GSH level, Ec-SOD activity, GAD67 expression, and GABA level in the PVN compared with the high salt group.Conclusion: Excessive salt intake not only activates oxidative stress but also induces the NLRP3-depensent inflammation and breaks the balance between inhibitory and excitability neurotransmitters in the PVN. Ec-SOD, as an essential anti-oxidative enzyme, eliminates the ROS in the PVN and decreases the blood pressure, probably through inhibiting the NLRP3-dependent inflammation and improving the excitatory neurotransmitter release in the PVN in the salt-induced hypertension.
- Published
- 2021
31. Effect of Different Parts (Leaf, Stem and Stalk) and Seasons (Summer and Winter) on the Chemical Compositions and Antioxidant Activity of Moringa oleifera
- Author
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Cheng-Ming Chang, Min-Lang Tsai, Sue-Ming Kang, and Ming-Chih Shih
- Subjects
Moringa oleifera ,antioxidative activity ,extract ,season ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Moringa oleifera, Lam. (Moringaceae) is grown world-wide in the tropics and sub-tropics of Asia and Africa and contains abundant various nutrients. This study describes the effect of different parts (leaf, stem and stalk) and seasons (summer and winter) on the chemical compositions and antioxidant activity of M. oleifera grown in Taiwan. The results showed that the winter samples of Moringa had higher ash (except the stalk part), calcium and phenolic compounds (except the leaf part) and stronger antioxidative activity than summer samples. The methanolic extract of Moringa showed strong scavenging effect of DPPH radicals and reducing power. The trend of antioxidative activity as a function of the part of Moringa was: leaf > stem > stalk for samples from both seasons investigated. The Moringa extract showed strong hydrogen peroxide scavenging activity and high Superoxide Dismutase (SOD) activity except the stalk part.
- Published
- 2011
- Full Text
- View/download PDF
32. Regulation of the Rhythmic Emission of Plant Volatiles by the Circadian Clock
- Author
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Lanting Zeng, Xiaoqin Wang, Ming Kang, Fang Dong, and Ziyin Yang
- Subjects
biosynthesis ,circadian clock ,emission ,plant volatile ,rhythm ,substrate ,transcription ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Like other organisms, plants have endogenous biological clocks that enable them to organize their metabolic, physiological, and developmental processes. The representative biological clock is the circadian system that regulates daily (24-h) rhythms. Circadian-regulated changes in growth have been observed in numerous plants. Evidence from many recent studies indicates that the circadian clock regulates a multitude of factors that affect plant metabolites, especially emitted volatiles that have important ecological functions. Here, we review recent progress in research on plant volatiles showing rhythmic emission under the regulation of the circadian clock, and on how the circadian clock controls the rhythmic emission of plant volatiles. We also discuss the potential impact of other factors on the circadian rhythmic emission of plant volatiles.
- Published
- 2017
- Full Text
- View/download PDF
33. Salusin-β in Intermediate Dorsal Motor Nucleus of the Vagus Regulates Sympathetic-Parasympathetic Balance and Blood Pressure
- Author
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Qi Chen, Yuehua Li, Yu-Ming Kang, Fen Zheng, Lu-Lu Wu, Jin-Hua Bo, Guo-Qing Zhu, and Feng Zhang
- Subjects
medicine.medical_specialty ,QH301-705.5 ,Medicine (miscellaneous) ,Endogeny ,General Biochemistry, Genetics and Molecular Biology ,Article ,dorsal motor nucleus of the vagus ,chemistry.chemical_compound ,Internal medicine ,salusin ,Heart rate ,medicine ,Tonic (music) ,Biology (General) ,chemistry.chemical_classification ,reactive oxygen species ,Reactive oxygen species ,Chemistry ,GABAA receptor ,Superoxide ,blood pressure ,sympathetic activity ,Dorsal motor nucleus ,Endocrinology ,Blood pressure ,paraventricular nucleus ,γ-aminobutyric acid - Abstract
The dorsal motor nucleus of the vagus (DMV) is known to control vagal activity. It is unknown whether the DMV regulates sympathetic activity and whether salusin-β in the DMV contributes to autonomic nervous activity. We investigated the roles of salusin-β in DMV in regulating sympathetic-parasympathetic balance and its underline mechanisms. Microinjections were carried out in the DMV and hypothalamic paraventricular nucleus (PVN) in male adult anesthetized rats. Renal sympathetic nerve activity (RSNA), blood pressure and heart rate were recorded. Immunohistochemistry for salusin-β and reactive oxidative species (ROS) production in the DMV were examined. Salusin-β was expressed in the intermediate DMV (iDMV). Salusin-β in the iDMV not only inhibited RSNA but also enhanced vagal activity and thereby reduced blood pressure and heart rate. The roles of salusin-β in causing vagal activation were mediated by NAD(P)H oxidase-dependent superoxide anion production in the iDMV. The roles of salusin-β in inhibiting RSNA were mediated by not only the NAD(P)H oxidase-originated superoxide anion production in the iDMV but also the γ-aminobutyric acid (GABA)A receptor activation in PVN. Moreover, endogenous salusin-β and ROS production in the iDMV play a tonic role in inhibiting RSNA. These results indicate that salusin-β in the iDMV inhibits sympathetic activity and enhances vagal activity, and thereby reduces blood pressure and heart rate, which are mediated by NAD(P)H oxidase-dependent ROS production in the iDMV. Moreover, GABAA receptor in the PVN mediates the effect of salusin-β on sympathetic inhibition. Endogenous salusin-β and ROS production in the iDMV play a tonic role in inhibiting sympathetic activity.
- Published
- 2021
34. Increasing Temperature Changes Flux into Multiple Biosynthetic Pathways for 2-Phenylethanol in Model Systems of Tea (Camellia sinensis) and Other Plants
- Author
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Ming Kang, Lanting Zeng, Fang Dong, Ziyin Yang, Haibo Tan, Naoharu Watanabe, Yinyin Liao, and Guotai Jian
- Subjects
0106 biological sciences ,Phenylacetaldehyde ,biology ,010401 analytical chemistry ,Phenylpyruvic acid ,food and beverages ,General Chemistry ,biology.organism_classification ,01 natural sciences ,Petunia ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Biosynthesis ,Aroma compound ,Camellia sinensis ,General Agricultural and Biological Sciences ,Flux (metabolism) ,Aroma ,010606 plant biology & botany - Abstract
2-Phenylethanol (2PE) is a representative aromatic aroma compound in tea (Camellia sinensis) leaves. However, its formation in tea remains unexplored. In our study, feeding experiments of [2H8]L-phenylalanine (Phe), [2H5]phenylpyruvic acid (PPA), or (E/Z)-phenylacetaldoxime (PAOx) showed that three biosynthesis pathways for 2PE derived from L-Phe occurred in tea leaves, namely, pathway I (via phenylacetaldehyde (PAld)), pathway II (via PPA and PAld), and pathway III (via (E/Z)-PAOx and PAld). Furthermore, increasing temperature resulted in increased flux into the pathway for 2PE from L-Phe via PPA and PAld. In addition, tomato fruits and petunia flowers also contained the 2PE biosynthetic pathway from L-Phe via PPA and PAld and increasing temperatures led to increased flux into this pathway, suggesting that such a phenomenon might be common among most plants containing 2PE. This represents a characteristic example of changes in flux into the biosynthesis pathways of volatile compounds in plants in response to stresses.
- Published
- 2019
35. Chemical Stimulation of Renal Tissue Induces Sympathetic Activation and a Pressor Response via the Paraventricular Nucleus in Rats
- Author
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Qi Chen, Yu-Ming Kang, Yun Qiu, Chao Ye, Guo-Qing Zhu, Hong Zhou, Yuehua Li, Feng Zhang, Ai-Dong Chen, and Jue-Jin Wang
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Mean arterial pressure ,Sympathetic Nervous System ,Physiology ,Blood Pressure ,Bradykinin ,Kidney ,urologic and male genital diseases ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Heart Rate ,Internal medicine ,Reflex ,Heart rate ,Animals ,Medicine ,Arterial Pressure ,Denervation ,business.industry ,Angiotensin II ,General Neuroscience ,General Medicine ,Stimulation, Chemical ,Rats ,030104 developmental biology ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Hypothalamus ,Capsaicin ,Hypertension ,Original Article ,business ,Proto-Oncogene Proteins c-fos ,030217 neurology & neurosurgery ,Paraventricular Hypothalamic Nucleus - Abstract
Sympathetic activation and the kidney play critical roles in hypertension and chronic heart failure. The role of the kidney in sympathetic activation is still not well known. In this study, we revealed an excitatory renal reflex (ERR) in rats induced by chemical stimulation of the kidney that regulated sympathetic activity and blood pressure. The ERR was induced by renal infusion of capsaicin, and evaluated by the changes in renal sympathetic outflow, blood pressure, and heart rate. Renal infusion of capsaicin dose-dependently increased the contralateral renal sympathetic nerve activity, mean arterial pressure, and heart rate. Capsaicin in the cortico-medullary border had greater effects than in the cortex or medulla. Intravenous infusion of capsaicin had no significant effects. The effects of renal infusion of capsaicin were abolished by ipsilateral renal denervation, but were not affected by bilateral sinoaortic denervation. Renal infusion of capsaicin increased the ipsilateral renal afferent activity. The ERR was also induced by renal infusion of bradykinin, adenosine, and angiotensin II, but not by ATP. Renal infusion of capsaicin increased c-Fos expression in the paraventricular nucleus (PVN) of hypothalamus. Lesion of neurons in the PVN with kainic acid abolished the capsaicin-induced ERR. These findings indicate that chemical stimulation of kidney causes an excitatory reflex, leading to sympathetic activation, pressor response, and accelerated heart rate. The PVN is an important central nucleus in the pathway of the ERR. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12264-019-00417-1) contains supplementary material, which is available to authorized users.
- Published
- 2019
36. Infusion of Melatonin Into the Paraventricular Nucleus Ameliorates Myocardial Ischemia–Reperfusion Injury by Regulating Oxidative Stress and Inflammatory Cytokines
- Author
-
Xiao-Jing Yu, Chao Zhang, Yu-Ming Kang, Wensheng Chen, and Jin-Bao Yang
- Subjects
0301 basic medicine ,Male ,Sympathetic Nervous System ,inflammatory cytokines ,Anti-Inflammatory Agents ,Myocardial Infarction ,melatonin ,030204 cardiovascular system & hematology ,medicine.disease_cause ,Antioxidants ,Ventricular Function, Left ,Rats, Sprague-Dawley ,0302 clinical medicine ,chemistry.chemical_classification ,Ejection fraction ,biology ,myocardial ischemia–reperfusion injury ,Infusions, Intraventricular ,Cytokines ,Original Article ,paraventricular nucleus ,Inflammation Mediators ,Cardiology and Cardiovascular Medicine ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Signal Transduction ,medicine.medical_specialty ,endocrine system ,Myocardial Reperfusion Injury ,Proinflammatory cytokine ,Norepinephrine (medication) ,Superoxide dismutase ,Melatonin ,03 medical and health sciences ,Internal medicine ,medicine ,Animals ,Pharmacology ,Reactive oxygen species ,business.industry ,Myocardium ,Stroke Volume ,medicine.disease ,Disease Models, Animal ,Oxidative Stress ,030104 developmental biology ,Endocrinology ,chemistry ,biology.protein ,business ,Reperfusion injury ,Oxidative stress ,Paraventricular Hypothalamic Nucleus - Abstract
Melatonin, the receptors for which are abundant in the hypothalamic paraventricular nucleus (PVN), can protect the heart from myocardial ischemia–reperfusion (MI/R) injury. The aim of this study was to determine whether the infusion of melatonin into the PVN protects the heart from MI/R injury by suppressing oxidative stress or regulating the balance between proinflammatory cytokines and anti-inflammatory cytokines in MI/R rats. Male Sprague–Dawley rats were treated with a bilateral PVN infusion of melatonin. MI/R operation was performed 1 week after infusion. At the end of the third week after the infusion, all the rats were euthanized. This was followed by immunohistochemistry and immunofluorescence studies of the rats. MI/R rats showed larger infarct size, increased left ventricular (LV) end-diastolic volume, and decreased LV ejection fraction and LV fractional shortening. Moreover, MI/R rats had a higher level of norepinephrine in the plasma, heart, and PVN; higher PVN levels of reactive oxygen species, NOX2, NOX4, IL-1β, and NF-κB activity; and lower PVN levels of copper/zinc superoxide dismutase (Cu/Zn-SOD) and IL-10 compared with the sham group. Melatonin infusion in PVN reduced LV end-diastolic volume, norepinephrine, reactive oxygen species, NOX2, NOX4, IL-1β, and NF-κB activity, and increased LV ejection fraction, LV fractional shortening, Cu/Zn-SOD, and IL-10. Overall, these results suggest that the infusion of melatonin ameliorates sympathetic nerve activity and MI/R injury by attenuating oxidative stress and inflammatory cytokines in the PVN of MI/R rats.
- Published
- 2019
37. Lycopene cyclases determine high α-/β-carotene ratio and increased carotenoids in bananas ripening at high temperatures
- Author
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Donald Grierson, Xiumin Fu, Yueming Jiang, Ming Kang, Ziyin Yang, Xuewu Duan, Sihua Cheng, Bingzhi Huang, and Chao Feng
- Subjects
Light ,medicine.medical_treatment ,01 natural sciences ,Analytical Chemistry ,chemistry.chemical_compound ,0404 agricultural biotechnology ,Biosynthesis ,medicine ,Food science ,Intramolecular Lyases ,Carotenoid ,Chromatography, High Pressure Liquid ,chemistry.chemical_classification ,Sequence Analysis, RNA ,010401 analytical chemistry ,Carotene ,Temperature ,food and beverages ,Musa ,Ripening ,04 agricultural and veterinary sciences ,General Medicine ,beta Carotene ,Carotenoids ,040401 food science ,Lycopene ,0104 chemical sciences ,Enzyme ,chemistry ,RNA, Plant ,Fruit ,Postharvest ,Flux (metabolism) ,Food Science - Abstract
Bananas are a recommended food source to alleviate vitamin A deficiency because they contain a high ratio of provitamin A precursors. The objective of this study was to investigate carotenoid accumulation pattern in banana fruits during postharvest ripening and the mechanisms regulating this process. Ripe banana pulp had an unusually high α-/β-carotene ratio (1.05), and the carotenoid contents increased (p ≤ 0.05) under light and high temperature. We analyzed the sequences, transcript levels, and functions of genes involved in carotenoid synthesis. The high ratio of α-/β-carotene in ripe banana fruit was explained by the high flux to the α-carotene biosynthetic pathway, as reflected by high transcript levels of LCYE, and the weak flux to the β-carotene branch of the biosynthetic pathway due to inactive MaLCYB1.2. High temperature during ripening up-regulated the transcript levels of genes involved in the α- and β-carotene biosynthesis pathways and the activities of their encoded enzymes.
- Published
- 2019
38. Asymmetric Synthesis of β-Aryl β-Imido Sulfones Using Rhodium Catalysts with Chiral Diene Ligands: Synthesis of Apremilast
- Author
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Ming Kang Tsai, Julian P. Henschke, Balraj Gopula, Ting Shen Kuo, Ping Yu Wu, Hsyueh Liang Wu, Jia Hong Jian, Jin Fong Syu, Wei Sian Li, and Meng Chi Hsieh
- Subjects
inorganic chemicals ,Diene ,010405 organic chemistry ,organic chemicals ,Aryl ,Organic Chemistry ,Enantioselective synthesis ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Combinatorial chemistry ,0104 chemical sciences ,Catalysis ,Sulfone ,Rhodium ,chemistry.chemical_compound ,chemistry ,heterocyclic compounds ,Stereoselectivity ,Physical and Theoretical Chemistry ,Enantiomer - Abstract
A chiral rhodium(I)-diene catalyst enabled the one-step synthesis of β-aryl β-imido sulfones under mild reaction conditions. By selection of the chiral diene ligand L1a or L2, each enantiomer of the chiral β-aryl β-imido sulfone target can be accessed with high stereoselectivity. Demonstration of the scope of the reaction, which includes the synthesis of an N-protected chiral β-amino β-phenyl sulfone, culminated with the efficient synthesis of the heteroatom-rich active pharmaceutical ingredient apremilast.
- Published
- 2019
39. Carbon Monoxide Attenuates High Salt-Induced Hypertension While Reducing Pro-inflammatory Cytokines and Oxidative Stress in the Paraventricular Nucleus
- Author
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Jie Qi, Dong-Dong Zhang, Guo-Rui Xin, Yan-Mei Chen, Yan-Feng Liang, Xiao-Lian Shi, Kai-Li Liu, Wei Cui, Hong-Li Gao, Kai B Kang, Li-Yan Fu, Xiao-Jing Yu, and Yu-Ming Kang
- Subjects
Male ,endocrine system ,medicine.medical_specialty ,Antioxidant ,medicine.medical_treatment ,Anti-Inflammatory Agents ,Endogeny ,030204 cardiovascular system & hematology ,Toxicology ,medicine.disease_cause ,Antioxidants ,Proinflammatory cytokine ,Norepinephrine (medication) ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Organometallic Compounds ,medicine ,Animals ,Arterial Pressure ,Sodium Chloride, Dietary ,Molecular Biology ,Microinjection ,Antihypertensive Agents ,chemistry.chemical_classification ,Carbon Monoxide ,Reactive oxygen species ,Rats, Inbred Dahl ,Chemistry ,NOX4 ,Disease Models, Animal ,Oxidative Stress ,Endocrinology ,Cyclooxygenase 2 ,030220 oncology & carcinogenesis ,Heme Oxygenase (Decyclizing) ,Hypertension ,Cytokines ,Inflammation Mediators ,Cardiology and Cardiovascular Medicine ,hormones, hormone substitutes, and hormone antagonists ,Oxidative stress ,Paraventricular Hypothalamic Nucleus ,medicine.drug - Abstract
Carbon monoxide (CO) presents anti-inflammatory and antioxidant activities as a new gaseous neuromessenger produced by heme oxygenase-1 (HO-1) in the body. High salt-induced hypertension is relevant to the levels of pro-inflammatory cytokines (PICs) and oxidative stress in the hypothalamic paraventricular nucleus (PVN). We explored whether CO in PVN can attenuate high salt-induced hypertension by regulating PICs or oxidative stress. Male Dahl Salt-Sensitive rats were fed high-salt (8% NaCl) or normal-salt (0.3% NaCl) diet for 4 weeks. CORM-2, ZnPP IX, or vehicle was microinjected into bilateral PVN for 6 weeks. High-salt diet increased the levels of MAP, plasma norepinephrine (NE), reactive oxygen species (ROS), and the expressions of COX2, IL-1β, IL-6, NOX2, and NOX4 significantly in PVN (p
- Published
- 2019
40. Highly efficient nitrogen and carbon coordinated N–Co–C electrocatalysts on reduced graphene oxide derived from vitamin-B12 for the hydrogen evolution reaction
- Author
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Tsu-Chin Chou, Ming Kang Tsai, Jyh-Fu Lee, Kuei-Hsien Chen, Wei-Fu Chen, Palani Sabhapathy, Yan-Gu Lin, Amr Sabbah, Indrajit Shown, Li-Chyong Chen, and Chen Cheng Liao
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Materials science ,Hydrogen ,Renewable Energy, Sustainability and the Environment ,Graphene ,Inorganic chemistry ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Overpotential ,021001 nanoscience & nanotechnology ,Catalysis ,law.invention ,Metal ,chemistry.chemical_compound ,chemistry ,law ,visual_art ,visual_art.visual_art_medium ,Water splitting ,General Materials Science ,0210 nano-technology ,Cobalt - Abstract
Exploring electrocatalysts composed of earth-abundant elements for a highly efficient hydrogen evolution reaction (HER) is scientifically and technologically important for electrocatalytic water splitting. In this work, we report HER properties of acid treated pyrolyzed vitamin B12 supported on reduced graphene oxide (B12/G800A) that shows an extraordinarily enhanced catalytic activity with low overpotential (115 mV vs. RHE at 10 mA cm−2), which is better than that of most traditional nonprecious metal catalysts in acidic media. Stability tests through long-term potential cycles and at a constant current density confirm the exceptional durability of the catalyst. Notably, the B12/G800A catalyst exhibits extremely high turnover frequencies per cobalt site in acid, for example, 0.85 and 11.46 s−1 at overpotentials of 100 and 200 mV, respectively, which are higher than those reported for other scalable non-precious metal HER catalysts. Moreover, it has been conjectured that the covalency of Co–C and Co–N bonds affects HER activities by comparing the extended X-ray absorption fine structure (EXAFS) spectra of the B12/G800A. High-temperature treatment can modify the Co-corrin structure of B12 to form Co–C bonds along with Co–N, which broadens the band of cobalt, essentially lowering the d-band center from its Fermi level. The lower d-band center leads to a moderate hydrogen binding energy, which is favorable for hydrogen adsorption and desorption.
- Published
- 2019
41. Visualization of silica dispersion states in silicone rubber by fluorescent labeling
- Author
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Lixian Song, Ai Lu, Kexu Chen, Lin Chen, Rong Sun, and Ming Kang
- Subjects
chemistry.chemical_classification ,Toughness ,Fluorescence-lifetime imaging microscopy ,Materials science ,Mechanical Engineering ,Composite number ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Silicone rubber ,01 natural sciences ,Fluorescence ,Dissociation (chemistry) ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Natural rubber ,Mechanics of Materials ,visual_art ,visual_art.visual_art_medium ,General Materials Science ,Composite material ,0210 nano-technology - Abstract
The internal dispersion structure of silica fillers in polymer matrix is significant for design and fabricating high-performance polymer composite. In order to explore the relationship between fillers spatial dispersion states and mechanical properties, we use superficial fluorescent labeling to achieve fillers visualization in polymer matrix with laser scanning confocal microscopy. Through the effect of fluorescent silane coupling agent, the uniform red fluorescence characteristics were shown on the silica surface. The 2D-planar and 3D-spatial dispersion states of silica fillers in rubber matrix can be accurately observed with fluorescence imaging technology. The results by Avizo software statistics show that high-content silica fillers in composite tend to undergo dissociation of aggregates. These dissociated small volume aggregates which facilitate the interaction between particles and rubber matrix to dissipate mechanical energy effectively and rapidly improve rubber toughness. This successful visualization method opens a new avenue in spatial dispersion description of fillers aggregates in organic–inorganic composite.
- Published
- 2018
42. Fast Living Polymerization and Helix-Sense-Selective Polymerization of Diazoacetates Using Air-Stable Palladium(II) Catalysts
- Author
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Zong-Quan Wu, Shu-Ming Kang, Jia-Hong Chu, Xun-Hui Xu, and Na Liu
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Denticity ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Catalysis ,0104 chemical sciences ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Monomer ,chemistry ,Polymerization ,Helix ,Polymer chemistry ,Living polymerization ,0210 nano-technology ,Phosphine ,Palladium - Abstract
In this work, air-stable palladium(II) catalysts bearing bidentate phosphine ligands were designed and prepared, which could initiate fast and living polymerizations of various diazoacetate monomers under mild conditions. The polymerization afforded the desired polymers in high yields with controlled molecular weights ( M
- Published
- 2018
43. Chronic Intracerebroventricular Infusion of Metformin Inhibits Salt-Sensitive Hypertension via Attenuation of Oxidative Stress and Neurohormonal Excitation in Rat Paraventricular Nucleus
- Author
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Wei Cui, Yi-Kang Hou, Guo-Qing Zhu, Hong-Bao Li, Bin Liang, Ying Li, Wen-Jie Xia, Hong-Li Gao, Huiyu Yang, Wensheng Chen, Ya-Nan Zhao, Zhi-Ming Yang, Qing Su, Yu-Ming Kang, Xiao-Jing Yu, and Kai-Li Liu
- Subjects
Male ,0301 basic medicine ,medicine.medical_specialty ,Mean arterial pressure ,Physiology ,medicine.disease_cause ,Inhibitory postsynaptic potential ,Antioxidants ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Arterial Pressure ,Sodium Chloride, Dietary ,chemistry.chemical_classification ,Neurotransmitter Agents ,Reactive oxygen species ,Oxidase test ,General Neuroscience ,digestive, oral, and skin physiology ,General Medicine ,Metformin ,Rats ,Oxidative Stress ,Infusions, Intraventricular ,030104 developmental biology ,Endocrinology ,chemistry ,Hypertension ,Excitatory postsynaptic potential ,Original Article ,NAD+ kinase ,Reactive Oxygen Species ,030217 neurology & neurosurgery ,Oxidative stress ,Paraventricular Hypothalamic Nucleus ,medicine.drug - Abstract
Metformin (MET), an antidiabetic agent, also has antioxidative effects in metabolic-related hypertension. This study was designed to determine whether MET has anti-hypertensive effects in salt-sensitive hypertensive rats by inhibiting oxidative stress in the hypothalamic paraventricular nucleus (PVN). Salt-sensitive rats received a high-salt (HS) diet to induce hypertension, or a normal-salt (NS) diet as control. At the same time, they received intracerebroventricular (ICV) infusion of MET or vehicle for 6 weeks. We found that HS rats had higher oxidative stress levels and mean arterial pressure (MAP) than NS rats. ICV infusion of MET attenuated MAP and reduced plasma norepinephrine levels in HS rats. It also decreased reactive oxygen species and the expression of subunits of NAD(P)H oxidase, improved the superoxide dismutase activity, reduced components of the renin-angiotensin system, and altered neurotransmitters in the PVN. Our findings suggest that central MET administration lowers MAP in salt-sensitive hypertension via attenuating oxidative stress, inhibiting the renin-angiotensin system, and restoring the balance between excitatory and inhibitory neurotransmitters in the PVN.
- Published
- 2018
44. The role of metal-oxo intermediate to oxygen reduction reaction catalysis: A theoretical investigation using nitrogen-substituted carbon nanotube models
- Author
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Ming Kang Tsai and Yu Te Chan
- Subjects
Chemistry ,Graphene ,chemistry.chemical_element ,02 engineering and technology ,Surfaces and Interfaces ,Carbon nanotube ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electrochemistry ,01 natural sciences ,Nitrogen ,0104 chemical sciences ,Surfaces, Coatings and Films ,law.invention ,Catalysis ,Metal ,Transition metal ,law ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Physical chemistry ,Electric potential ,0210 nano-technology - Abstract
The electrochemical oxygen reduction mechanism (ORR) using the transition metal embedded and nitrogen substituted carbon-material models – TM–N4L (TM = Fe, Ru, Os, Co, Rh, Ir, Ni, Pt, and Cu; L = CNT(5,5) and graphene) are investigated. The models of group 9 elements (Co, Rh, Ir) appear to give the most uniform stepwise free energy along the 4e reduction pathway in comparison with the ideal electrochemical steps, and that could provide the most stable electric potential generation in fuels cell applications. The free energy of formation for the oxo intermediates is the determinant factor to cause the deviation from the ideal steps. The models of group 8 elements (Fe, Ru, Os) preferentially form multiple coordination bonds with the oxo intermediate via the empty d-orbitals of metal centers. In the 2e vs. 4e reduction comparison, the Fe–N4L models are found to favor 4e pathway because of the accessible O–O bond breaking barrier of Fe(OOH) intermediate around 0.5 eV while the Co models could favor the 2e pathway to form HOOH(aq). This theoretical analysis of metal-based chemistry for ORR catalysis could be helpful to the future ORR catalyst development.
- Published
- 2018
45. Real-Time Imaging of Free Radicals for Mitochondria-Targeting Hypoxic Tumor Therapy
- Author
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Ying Tang, Miao-Deng Liu, Ming-Kang Zhang, Meng-Yun Peng, Bo-Ru Xie, Yu Zhang, Chu-Xin Li, Xian-Zheng Zhang, and Xiao-Qiang Wang
- Subjects
Free Radicals ,Radical ,Metal Nanoparticles ,Apoptosis ,Mammary Neoplasms, Animal ,Bioengineering ,Real time imaging ,02 engineering and technology ,Mitochondrion ,010402 general chemistry ,01 natural sciences ,Mice ,Drug Delivery Systems ,In vivo ,Cell Line, Tumor ,medicine ,Animals ,General Materials Science ,Inner mitochondrial membrane ,Hypoxic tumor ,Chemistry ,Mechanical Engineering ,General Chemistry ,Hypoxia (medical) ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,In vitro ,Mitochondria ,Molecular Imaging ,0104 chemical sciences ,Cancer research ,Tumor Hypoxia ,Female ,Gold ,medicine.symptom ,0210 nano-technology - Abstract
Free radicals have emerged as new-type and promising candidates for hypoxic tumor treatment, and further study of their therapeutic mechanism by real-time imaging is of great importance to explore their biomedical applications. Herein, we present a smart free-radical generator AuNC-V057-TPP for hypoxic tumor therapy; the AuNC-V057-TPP not only exhibits good therapeutic effect under both hypoxic and normoxic conditions but also can monitor the release of free radicals in real-time both in vitro and in vivo. What is more, with the mitochondria-targeting ability, the AuNC-V057-TPP is demonstrated with improved antitumor efficacy through enhanced free radical level in mitochondria, which leads to mitochondrial membrane damage and ATP production reduction and finally induces cancer cell apoptosis.
- Published
- 2018
46. Blockade of Endogenous Angiotensin-(1–7) in Hypothalamic Paraventricular Nucleus Attenuates High Salt-Induced Sympathoexcitation and Hypertension
- Author
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Li-Yan Fu, Xiao-Jing Yu, Wei Cui, Xiao-Lian Shi, Wen-Sheng Chen, Yu-Ming Kang, Qing Su, Jian-Jun Mu, Guo-Qing Zhu, Ying Li, Kai-Li Liu, Philip J. Ebenezer, Joseph Francis, Yu-Wang Miao, Hong-Bao Li, and Yi-Kang Hou
- Subjects
Male ,0301 basic medicine ,endocrine system ,Mean arterial pressure ,medicine.medical_specialty ,Physiology ,Blood Pressure ,Endogeny ,medicine.disease_cause ,Antioxidants ,Proinflammatory cytokine ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Renin–angiotensin system ,medicine ,Animals ,Sodium Chloride, Dietary ,Microinjection ,Chemistry ,General Neuroscience ,Antagonist ,General Medicine ,Peptide Fragments ,Oxidative Stress ,030104 developmental biology ,Endocrinology ,Blood pressure ,Hypertension ,Original Article ,Angiotensin I ,Reactive Oxygen Species ,hormones, hormone substitutes, and hormone antagonists ,030217 neurology & neurosurgery ,Oxidative stress ,Paraventricular Hypothalamic Nucleus - Abstract
Angiotensin (Ang)-(1–7) is an important biologically-active peptide of the renin-angiotensin system. This study was designed to determine whether inhibition of Ang-(1–7) in the hypothalamic paraventricular nucleus (PVN) attenuates sympathetic activity and elevates blood pressure by modulating pro-inflammatory cytokines (PICs) and oxidative stress in the PVN in salt-induced hypertension. Rats were fed either a high-salt (8% NaCl) or a normal salt diet (0.3% NaCl) for 10 weeks, followed by bilateral microinjections of the Ang-(1–7) antagonist A-779 or vehicle into the PVN. We found that the mean arterial pressure (MAP), renal sympathetic nerve activity (RSNA), and plasma norepinephrine (NE) were significantly increased in salt-induced hypertensive rats. The high-salt diet also resulted in higher levels of the PICs interleukin-6, interleukin-1beta, tumor necrosis factor alpha, and monocyte chemotactic protein-1, as well as higher gp91(phox) expression and superoxide production in the PVN. Microinjection of A-779 (3 nmol/50 nL) into the bilateral PVN of hypertensive rats not only attenuated MAP, RSNA, and NE, but also decreased the PICs and oxidative stress in the PVN. These results suggest that the increased MAP and sympathetic activity in salt-induced hypertension can be suppressed by blockade of endogenous Ang-(1–7) in the PVN, through modulation of PICs and oxidative stress.
- Published
- 2018
47. Exosome-Mediated Transfer of ACE (Angiotensin-Converting Enzyme) From Adventitial Fibroblasts of Spontaneously Hypertensive Rats Promotes Vascular Smooth Muscle Cell Migration
- Author
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Xiao-Qing Xiong, Yun Qiu, Xing-Sheng Ren, Ying-Hao Zang, Jue-Jin Wang, Chao Ye, Yu-Ming Kang, Ying Tong, Qi Chen, Yuehua Li, and Guo-Qing Zhu
- Subjects
0301 basic medicine ,Adventitia ,Captopril ,Vascular smooth muscle ,Angiotensin-Converting Enzyme Inhibitors ,Peptidyl-Dipeptidase A ,Vascular Remodeling ,030204 cardiovascular system & hematology ,Exosomes ,Benzylidene Compounds ,Rats, Inbred WKY ,Exosome ,Losartan ,Muscle, Smooth, Vascular ,Angiotensin Receptor Antagonists ,03 medical and health sciences ,0302 clinical medicine ,Cell Movement ,Rats, Inbred SHR ,Internal Medicine ,medicine ,Animals ,Vascular structure ,cardiovascular diseases ,Aniline Compounds ,Chemistry ,Fibroblasts ,musculoskeletal system ,Microvesicles ,Rats ,Cell biology ,030104 developmental biology ,Gene Knockdown Techniques ,ACE - Angiotensin-converting enzyme ,Hypertension ,cardiovascular system ,Vascular smooth muscle cell migration ,Homeostasis ,circulatory and respiratory physiology ,medicine.drug - Abstract
Migration of vascular smooth muscle cells (VSMCs) is pivotal for vascular remodeling in hypertension. Vascular adventitial fibroblasts (AFs) are important in the homeostasis of vascular structure. This study is designed to investigate the roles of AF exosomes (AFE) in VSMC migration and underling mechanism. Primary VSMCs and AFs were obtained from the aorta of spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. VSMC migration was evaluated with Boyden chamber assay and wound healing assay. AFE from WKY rats and SHR were isolated and identified. AFE from SHR promoted but AFE from WKY rats had no significant effect on VSMC migration. The effects of AFE on VSMC migration were prevented by an exosome inhibitor GW4869, an AT 1 R (Ang II [angiotensin II] type 1 receptor) antagonist losartan, or an inhibitor of ACE (angiotensin-converting enzyme) captopril. ACE contents and activity were much higher in AFE from SHR than those from WKY rats. There were no significant difference in Ang II and AT 1 R mRNA and protein levels between AFE from SHR and AFE from WKY rats. AFE from SHR increased Ang II and ACE contents and ACE activity in VSMCs of WKY rats and SHR. The changes of Ang II contents and ACE activity were prevented by captopril. ACE knockdown in AFs reduced ACE contents and activity in AFE from SHR and inhibited AFE-induced migration of VSMCs of WKY rats and those of SHR. These results indicate that exosomes from AFs of SHR transfer ACE to VSMCs, which increases Ang II levels and activates AT 1 R in VSMCs and thereby promotes VSMC migration.
- Published
- 2018
48. Inhibition of Maternal c-Src Ameliorates the Male Offspring Hypertension by Suppressing Inflammation and Neurotransmitters in the Paraventricular Nucleus
- Author
-
Xiao-Jing Yu, Yu-Ming Kang, Qiu-Yue Yi, Qing Yang, Hong-Bao Li, Kai-Li Liu, Xiao-Min Wang, Wen-Jie Xia, and Qing Su
- Subjects
Male ,medicine.medical_specialty ,Offspring ,Dasatinib ,Inflammation ,Toxicology ,Proinflammatory cytokine ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Pregnancy ,Lactation ,Internal medicine ,medicine ,Animals ,Arterial Pressure ,Salt intake ,Sodium Chloride, Dietary ,Neurotransmitter ,Molecular Biology ,Protein Kinase Inhibitors ,Antihypertensive Agents ,Neurotransmitter Agents ,business.industry ,NF-kappa B ,medicine.disease ,Disease Models, Animal ,Blood pressure ,medicine.anatomical_structure ,Endocrinology ,src-Family Kinases ,chemistry ,Maternal Exposure ,Prenatal Exposure Delayed Effects ,Hypertension ,Female ,medicine.symptom ,Inflammation Mediators ,Mitogen-Activated Protein Kinases ,Cardiology and Cardiovascular Medicine ,business ,Paraventricular Hypothalamic Nucleus ,Signal Transduction - Abstract
Long-term maternal salt intake induces the hypertension in offspring. Numerous studies have also indicated that high-salt diet causes the inflammation and an imbalance in neurotransmitters in the paraventricular nucleus (PVN) which increases the blood pressure and sympathetic activity. This study aimed to explore whether maternal salt intake induces hypertension in their male offspring by increasing the inflammation and changing the neurotransmitters balance in the paraventricular nucleus of offspring. This study includes two parts: Part I to explore the effect of high-salt diet on pregnant rats and the changes in inflammation and neurotransmitters in their male offspring PVN; Part II to reveal the influence on their offspring of bilateral PVN infusion of c-Src inhibitor dasatinib (DAS) in pregnant rats fed a high-salt diet. Maternal high-salt diet intake during copulation, pregnancy, and lactation impacted the offspring mean arterial pressure (MAP) and elevated the offspring PVN levels of p-Src, proinflammatory cytokines, and excitatory neurotransmitters. Bilateral PVN infusion of a c-Src inhibitor combined with maternal high-salt diets decreased MAP in the offspring. The infusion was also shown to suppress the Src-induced MAPK/NF-κB signaling pathway (p38 MAPK, JNK, Erk1/2), which attenuates inflammatory reactions. Finally, bilateral PVN infusion of the Src inhibitor in pregnant rat with high-salt diets improved the levels of inhibitory neurotransmitters in offspring PVN, which restored the excitatory-inhibitory neurotransmitter balance in male offspring. High-salt diets increase sympathetic activity and blood pressure in adult offspring, probably by activating the c-Src/MAPKs/NF-κB signaling pathway-induced inflammation. Moreover, NF-κB disrupts the downstream excitatory-inhibitory neurotransmitter balance in the PVN of male offspring.
- Published
- 2021
49. Paraventricular Nucleus Infusion of Oligomeric Proantho Cyanidins Improves Renovascular Hypertension
- Author
-
Kai-Li Liu, Ying Li, Kai B Kang, Yu-Ming Kang, Qiu-Yue Yi, Guo-Rui Xin, Yao-Jun Sun, Jie Qi, Li-Yan Fu, Xiao-Jing Liu, Ting-Ting Meng, and Xiao-Jing Yu
- Subjects
0301 basic medicine ,medicine.medical_specialty ,hypertension ,030204 cardiovascular system & hematology ,medicine.disease_cause ,neurotransmitters ,Renovascular hypertension ,lcsh:RC321-571 ,03 medical and health sciences ,Norepinephrine ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,medicine ,oxidative stress ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,oligomeric proantho cyanidins ,Original Research ,Tyrosine hydroxylase ,hypothalamic paraventricular nucleus ,General Neuroscience ,NOX4 ,medicine.disease ,030104 developmental biology ,Endocrinology ,Blood pressure ,Paraventricular nucleus of hypothalamus ,chemistry ,nervous system ,Nicotinamide adenine dinucleotide phosphate ,Oxidative stress ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug ,Neuroscience - Abstract
Oxidative stress plays an important role in the pathogenesis of hypertension. Oligomeric proantho cyanidins (OPC) is the main polyphenol presents in grape seed and is known for its potent antioxidant and anti-inflammatory properties. In the present study, we hypothesize that OPC can attenuate oxidative stress in the paraventricular nucleus of hypothalamus (PVN), ameliorate neurotransmitter imbalance, decrease the blood pressure and sympathetic activity in renovascular hypertensive rats. After induction of renovascular hypertension by the two-kidney one-clip (2K-1C) method, male Sprague-Dawley rats received chronic bilateral PVN infusion of OPC (20 μg/h) or vehicle via osmotic minipump for 4 weeks. We found that hypertension induced by 2K-1C was associated with the production of reactive oxygen species (ROS) in the PVN. Infusion of OPC in the PVN significantly reduced the systolic blood pressure and norepinephrine in plasma of 2K-1C rats. In addition, PVN infusion of OPC decreased the level of ROS and the expression of stress-related nicotinamide adenine dinucleotide phosphate (NADPH) oxidases subunit NOX4, increased the levels of nuclear factor E2-related factor 2 (Nrf2) and antioxidant enzyme, balanced the content of cytokines, increased expression of glutamic acid decarboxylase and decreased the expression of tyrosine hydroxylase in the PVN of 2K-1C rats. Our findings provided strong evidence that PVN infusion of OPC inhibited the progression of renovascular hypertension through its potent anti-oxidative and anti-inflammatory function in the PVN.
- Published
- 2021
50. Dysregulation of the Excitatory Renal Reflex in the Sympathetic Activation of Spontaneously Hypertensive Rat
- Author
-
Chao Ye, Fen Zheng, Jing-Xiao Wang, Xiao-Li Wang, Qi Chen, Yue-Hua Li, Yu-Ming Kang, and Guo-Qing Zhu
- Subjects
Mean arterial pressure ,medicine.medical_specialty ,kidney ,hypertension ,Physiology ,Stimulation ,Pathogenesis ,chemistry.chemical_compound ,Spontaneously hypertensive rat ,Physiology (medical) ,Internal medicine ,Medicine ,QP1-981 ,Original Research ,Kidney ,business.industry ,blood pressure ,sympathetic activity ,Blood pressure ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Capsaicin ,Reflex ,business ,renal reflex ,circulatory and respiratory physiology - Abstract
Excessive sympathetic activation plays crucial roles in the pathogenesis of hypertension. Chemical stimulation of renal afferents increases the sympathetic activity and blood pressure in normal rats. This study investigated the excitatory renal reflex (ERR) in the development of hypertension in the spontaneously hypertensive rat (SHR). Experiments were performed in the Wistar-Kyoto rat (WKY) and SHR aged at 4, 12, and 24 weeks under anesthesia. Renal infusion of capsaicin was used to stimulate renal afferents, and thus, to induce ERR. The ERR was evaluated by the changes in the contralateral renal sympathetic nerve activity and mean arterial pressure. At the age of 4 weeks, the early stage with a slight or moderate hypertension, the ERR was more enhanced in SHR compared with WKY. The pressor response was greater than the sympathetic activation response in the SHR. At the age of 12 weeks, the development stage with severe hypertension, there was no significant difference in the ERR between the WKY and SHR. At the age of 24 weeks, the later stage of hypertension with long-term several hypertensions, the ERR was more attenuated in the SHR compared with the WKY. On the other hand, the pressor response to sympathetic activation due to the ERR was smaller at the age of 12 and 24 weeks than those at the age of 4 weeks. These results indicate that ERR is enhanced in the early stage of hypertension, and attenuated in the later stage of hypertension in the SHR. Abnormal ERR is involved in the sympathetic activation and the development of hypertension.
- Published
- 2021
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