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1.
Sci Total Environ ; 838(Pt 1): 156020, 2022 Sep 10.
Article in English | MEDLINE | ID: mdl-35595134

ABSTRACT

With the negative impact of climate change on the environment becoming more and more obvious, countries all over the world have strengthened their attention to environmental protection, the establishment of carbon emission trading mechanism is widely regarded as the most effective way to reduce carbon emissions. The design of carbon emission trading markets (ETMs) operation mechanisms and operational efficiency directly affect whether carbon ETM can cope with climate change and achieve its environmental protection purpose. In this study, we use multiple model synthesis to comprehensively evaluate the operation of carbon ETM, determine unreasonable modes of carbon ETM operation and propose suggestions for improvement. First, we propose a methodological framework to comprehensively evaluate the operational efficiency of carbon ETMs, and use the DCC-GARCH model to analyse information exchange and interaction between domestic and international carbon ETMs. Then, from the four dimensions of trading processes, law and inspection systems, the internal operation of carbon ETMs, and the impact of carbon ETM operation on the regional economy, 13 input-output indicators are selected to establish a super-DEA model to evaluate the efficiency of seven carbon ETMs. The results show that the spillover effect among various carbon ETMs is unstable, exchange between carbon ETMs is low. The operational efficiency of China's carbon ETMs is increasing each year, but there are significant differences in the operation efficiency levels of carbon ETMs. The system in Hubei has the highest super-DEA score, followed by that in Shenzhen, and those in Chongqing and Tianjin have lower scores. From the perspective of pilot projects with good operation, strong legal system constraints and reasonable operation mechanisms are important means to ensure operational efficiency.


Subject(s)
Carbon , Greenhouse Gases , Carbon/analysis , China , Climate Change , Efficiency , Greenhouse Gases/analysis
2.
Molecules ; 24(14)2019 Jul 23.
Article in English | MEDLINE | ID: mdl-31340585

ABSTRACT

The stems of Dendrobium loddigesii, a Chinese herb, are often used to treat diabetes and its polar extract is rich in shihunine, a water-soluble Orchidaceae alkaloid, but little is known about the anti-diabetes effects and mechanism of shihunine. This study investigated the anti-diabetic effect of a shihunine-rich extract of D. loddigesii (DLS) based on 3T3-L1 cells and db/db mice. The underlying mechanisms were primarily explored using Western blot analysis and immunohistochemical staining. The 3T3-L1 cell experiments showed that DLS can reduce the intracellular accumulation of oil droplets as well as triglycerides (p < 0.001) and promote the 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2deoxyglucose (2-NBDG) uptake of 3T3-L1 cells (p < 0.001). The animal experiments confirmed that after 8 weeks of DLS treatment, the body weight, fasting blood sugar, and serum lipid levels of mice were significantly lowered, and the oral glucose tolerance test and serum insulin level were significantly improved compared to the no-treatment diabetes mellitus group. Further histomorphology observation led to the conclusion that the quantities of islet cells were significantly increased and the increase in adipose cell size was significantly suppressed. The immunohistochemical test of pancreatic tissue revealed that DLS inhibited the expression of cleaved cysteine aspartic acid-specific protease 3 (cleaved caspase-3). Western blot experiments showed that DLS had agonistic effects on adenosine monophosphate (AMP)-activated protein kinase phosphorylation (p-AMPK) and increased the expression levels of peroxisome proliferator-activated receptor α (PPARα) and glucose transporter 4 (GLUT4) in liver or adipose tissues. These data suggest that the shihunine-rich extract of D. loddigesii is an anti-diabetic fraction of D. loddigesii. Under our experimental condition, DLS at a dose of 50 mg/kg has good anti-diabetic efficacy.


Subject(s)
Blood Glucose/drug effects , Dendrobium/chemistry , Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/pharmacology , Lactones/pharmacology , Plant Extracts/pharmacology , Pyrrolidines/pharmacology , 3T3-L1 Cells , 4-Chloro-7-nitrobenzofurazan/analogs & derivatives , 4-Chloro-7-nitrobenzofurazan/metabolism , AMP-Activated Protein Kinases/genetics , AMP-Activated Protein Kinases/metabolism , Animals , Biological Transport , Blood Glucose/metabolism , Caspase 3/genetics , Caspase 3/metabolism , Deoxyglucose/analogs & derivatives , Deoxyglucose/metabolism , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/physiopathology , Fasting , Gene Expression Regulation , Glucose Tolerance Test , Glucose Transporter Type 4/genetics , Glucose Transporter Type 4/metabolism , Hypoglycemic Agents/isolation & purification , Lactones/isolation & purification , Lipid Droplets/chemistry , Lipid Droplets/drug effects , Male , Mice , Mice, Transgenic , PPAR alpha/genetics , PPAR alpha/metabolism , Plant Extracts/chemistry , Plant Stems/chemistry , Pyrrolidines/isolation & purification , Signal Transduction , Triglycerides/antagonists & inhibitors , Triglycerides/metabolism
3.
Molecules ; 23(12)2018 Dec 07.
Article in English | MEDLINE | ID: mdl-30544624

ABSTRACT

Dendrobium is a traditional Chinese herb with anti-diabetic effects and has diverse bibenzyls as well as phenanthrenes. Little is known about Dendrobium polyphenols anti-diabetic activities, so, a rich-polyphenols extract of D. loddigesii (DJP) was used for treatment of diabetic db/db mice; the serum biochemical index and tissue appearance were evaluated. In order to gain an insight into the anti-diabetic mechanism, the oxidative stress index, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and gut microbiota modulation were determined by ELISA, immunohistochemistry or high throughput sequencing 16S rRNA gene. The results revealed that DJP had the effects to decrease the blood glucose, body weight, low density lipoprotein cholesterol (LDL-C) levels and increase insulin (INS) level in the mice. DJP improved the mice fatty liver and diabetic nephropathy. DJP showed the anti-oxidative abilities to reduce the malondialdehyde (MDA) level and increase the contents of superoxide dismutase (SOD), catalase (CAT) as well as glutathione (GSH). DJP exerted the anti-inflammatory effects of decreasing expression of IL-6 and TNF-α. After treatment of DJP, the intestinal flora balance of the mice was ameliorated, increasing Bacteroidetes to Firmicutes ratios as well as the relative abundance of Prevotella/Akkermansia and reducing the relative abundance of S24-7/Rikenella/Escherichia coli. The function's prediction of gut microbiota indicated that the microbial compositions involved carbohydrate metabolism or lipid metabolism were changed. This study revealed for the first time that DJP improves the mice symptoms of diabetes and complications, which might be due to the effects that DJP induced the decrease of inflammation as well as oxidative stress and improvement of intestinal flora balance.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Antioxidants/therapeutic use , Dendrobium/chemistry , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/microbiology , Gastrointestinal Microbiome/drug effects , Hypoglycemic Agents/therapeutic use , Polyphenols/therapeutic use , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Biodiversity , Blood Glucose/metabolism , Diabetes Mellitus, Experimental/blood , Glucose Tolerance Test , Hypoglycemic Agents/pharmacology , Interleukin-6/blood , Kidney/drug effects , Kidney/pathology , Lipids/blood , Liver/drug effects , Liver/pathology , Male , Mice, Inbred C57BL , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Polyphenols/pharmacology , Principal Component Analysis , Species Specificity , Tumor Necrosis Factor-alpha/blood
4.
Front Pharmacol ; 9: 540, 2018.
Article in English | MEDLINE | ID: mdl-29928229

ABSTRACT

Puerarin is an isoflavone isolated from Radix puerariae. Emerging evidence shown that puerarin possesses therapeutic benefits that aid in the prevention of cardiovascular diseases. In this study, we evaluated the effects of puerarin on oxidative stress and cardiac fibrosis induced by abdominal aortic banding (AB) and angiotensin II (AngII). We also investigated the mechanisms underlying this phenomenon. The results of histopathological analysis, as well as measurements of collagen expression and cardiac fibroblast proliferation indicated that puerarin administration significantly inhibited cardiac fibrosis induced by AB and AngII. These effects of puerarin may reflect activation of Nrf2/ROS pathway. This hypothesis is supported by observed decreases of reactive oxygen species (ROS), decreases Keap 1, increases Nrf2 expression and nuclear translocation, and decreases of collagen expressions in cardiac fibroblasts treated with a combination of puerarin and AngII. Inhibition of Nrf2 with specific Nrf2 siRNA or Nrf2 inhibitor brusatol attenuated anti-fibrotic and anti-oxidant effects of puerarin. The metabolic effects of puerarin were mediated by Nrf2 through upregulation of UDP-glucuronosyltransferase (UGT) 1A1. The Nrf2 agonist tBHQ upregulated protein expression of UGT1A1 over time in cardiac fibroblasts. Treatment with Nrf2 siRNA or brusatol dramatically decreased UGT1A1 expression in puerarin-treated fibroblasts. The results of chromatin immunoprecipitation-qPCR further confirmed that puerarin significantly increased binding of Nrf2 to the promoter region of Ugt1a1. Western blot analysis showed that puerarin significantly inhibited AngII-induced phosphorylation of p38-MAPK. A specific inhibitor of p38-MAPK, SB203580, decreased collagen expression, and ROS generation induced by AngII in cardiac fibroblast. Together, these results suggest that puerarin prevents cardiac fibrosis via activation of Nrf2 and inactivation of p38-MAPK. Nrf2 is the key regulator of anti-fibrotic effects and upregulates metabolic enzymes UGT1A1. Autoregulatory circuits between puerarin and Nrf2-regulated UGT1A1 attenuates side effects associated with treatment, but it does not weaken puerarin's pharmacological effects.

5.
J Biomed Nanotechnol ; 14(8): 1458-1470, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-29903060

ABSTRACT

Generally, nitric oxide (NO) is an important multi-functional cardioprotective soluble gas molecule. However, it may be detrimental when in excessive levels or combined with O2- a kind of reactive oxygen species (ROS)-to form ONOO-. The latter will rapidly decompose to highly reactive oxidant components. ROS will be abundantly produced during the ischemia/reperfusion (I/R) procedure. Therefore, an NO donor coupled with another antioxidant would be a more promising strategy for I/R treatment. In this study, we report on a novel self-assembly supramolecular hydrogel capable of constantly releasing both NO and curcumin (Cur) simultaneously, and we found that the combinational treatment of Cur and NO from the gel could efficiently reduce I/R injuries. The underlining mechanism revealed that the hydrogel could reduce the ROS level and thus inhibit the expression of the ROS-associated p38 MAPK/NF-κB signaling pathway. Moreover, the hydrogel also significantly suppressed over-stimulated autophagy and apoptosis during I/R treatment which was responsible for mediating severe post-ischemia myocardial cell death. The results indicated that our supramolecular hydrogel was a promising biomaterial for the treatment of myocardial I/R injuries.


Subject(s)
Autophagy , Myocardial Reperfusion Injury , Apoptosis , Humans , Hydrogels , Reactive Oxygen Species
6.
J Biomed Nanotechnol ; 14(2): 257-266, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-31352922

ABSTRACT

Supramolecular hydrogels have drawn increased attention because of their advantages in facile synthesis, biocompatibility, easy degradation and fast responses to external stimuli. Until now, the example of hydrogelators of pure natural resources has rarely been reported. Here, we report on a novel hydrogelator of a natural resource, puerarin, which could self-assemble to hydrogels with excellent antioxidant properties and tremendous acid resistance. Our PG-4 could overcome exogenous ROS injury and promote the survival rate of H2O2 treated MSCs by down-regulating SOD activity and MDA level by 21.6% and 28.7% respectively. In addition, utilizing the good acid resistance of PG-4, we investigated its application as an oral formulation. The dissolution rate of puerarin in intestinal-fluid analogue (87.8% at 12 hr) was much faster than that in gastric-fluid analogue (35.6% at 12 hr), which demonstrated that the majority of puerarin was diffused from PG-4 in simulated intestinal fluid. The corresponding pharmacokinetics parameters indicated that PG-4 remarkably improved the absorption of puerarin by oral administration.


Subject(s)
Isoflavones/chemistry , Antioxidants , Hydrogels , Hydrogen Peroxide
7.
Mol Divers ; 19(1): 123-34, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25273562

ABSTRACT

Influenza is an acute respiratory infectious disease caused by influenza viruses. Its subtype can be distinguished based on the antigenicity of two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). One of the main challenges in anti-influenza drug development is the quick evolution of drug resistance due to virus mutations. One solution to this problem is to develop dual-targeting anti-influenza agents. In this paper, a new rationally designed virtual screening protocol that combines structure-based approaches (molecular docking and molecular dynamic simulations) and ligand-based approaches (support vector machines and 3D shape & electrostatic similarity algorithms) is reported for the virtual screening of dual-targeting agents against HA and NA. The final hits came from the consensus of the ligand- and receptor-based knowledge of HA and NA and were tested using ADMET predictions. Evidence from the binding energy calculations and binding mode analyses suggested that several of the hits are promising as dual-targeting anti-influenza agents. The virtual screening protocol may also lead to the identification of innovative drugs in other fields.


Subject(s)
Antiviral Agents/chemistry , Drug Discovery/methods , Hemagglutinin Glycoproteins, Influenza Virus , Influenza A Virus, H5N1 Subtype , Molecular Dynamics Simulation , Neuraminidase , Viral Proteins , Antiviral Agents/therapeutic use , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Hemagglutinin Glycoproteins, Influenza Virus/metabolism , Humans , Influenza, Human/drug therapy , Influenza, Human/virology , Neuraminidase/antagonists & inhibitors , Neuraminidase/chemistry , Neuraminidase/metabolism , Support Vector Machine , Viral Proteins/antagonists & inhibitors , Viral Proteins/chemistry , Viral Proteins/metabolism
8.
J Chem Inf Model ; 53(10): 2757-64, 2013 Oct 28.
Article in English | MEDLINE | ID: mdl-24001302

ABSTRACT

High-performance computing (HPC) has become a state strategic technology in a number of countries. One hypothesis is that HPC can accelerate biopharmaceutical innovation. Our experimental data demonstrate that HPC can significantly accelerate biopharmaceutical innovation by employing molecular dynamics-based virtual screening (MDVS). Without using HPC, MDVS for a 10K compound library with tens of nanoseconds of MD simulations requires years of computer time. In contrast, a state of the art HPC can be 600 times faster than an eight-core PC server is in screening a typical drug target (which contains about 40K atoms). Also, careful design of the GPU/CPU architecture can reduce the HPC costs. However, the communication cost of parallel computing is a bottleneck that acts as the main limit of further virtual screening improvements for drug innovations.


Subject(s)
HIV Protease Inhibitors/chemistry , HIV Protease/chemistry , Molecular Dynamics Simulation , Neuraminidase/chemistry , PPAR alpha/chemistry , Small Molecule Libraries/chemistry , User-Computer Interface , Algorithms , Artificial Intelligence , Binding Sites , Databases, Chemical , Databases, Protein , Drug Discovery , High-Throughput Screening Assays/economics , High-Throughput Screening Assays/instrumentation , Humans , Ligands , Molecular Docking Simulation , Neuraminidase/antagonists & inhibitors , PPAR alpha/antagonists & inhibitors , Protein Binding , Structure-Activity Relationship , Thermodynamics
9.
Hum Reprod ; 22(10): 2743-50, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17566014

ABSTRACT

BACKGROUND: Cyclosporin A (CsA) is an immunosuppressent which is used for preventing allograft rejection. Little is known, however, about the effect of CsA on the materno-fetal relationship. Our aim was to probe into the effect of CsA on the invasiveness of human first-trimester trophoblast cells and explore possible molecules involved, with a view to providing a new therapeutic approach for pregnancy complications with trophoblast disorder. METHODS: The effects of CsA on invasion of the first-trimester human trophoblasts were examined by matrigel invasion assay, and the transcription, translation and proteolytic activity of matrix metalloproteinase (MMP-9) and MMP-2 in these cells were estimated by RT-PCR, in-cell Western and zymography, respectively. The phosphorylation level of extracellular-signal related kinase (ERK) 1/2 in trophoblasts induced by CsA was also evaluated by in-cell Western. RESULTS: CsA increased the invasive index of first-trimester human trophoblasts (P < 0.01), as well as the messenger RNA, protein levels (both P < 0.01) and proteolytic activity (P < 0.05) of MMP-9 and MMP-U0126, a mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor, inhibited the enhanced invasiveness and activity of MMP-9 and MMP-in these cells induced by CsA. In addition, CsA activated the ERK1/2 in a time-dependent manner. CONCLUSIONS: CsA improves the invasiveness and activity of MMP 9 and MMP 2 in vitro of the first-trimester human trophoblast cells through activation of mitogen-activated protein kinase/extracellular-signal related kinase (ERK) 1/2 signaling pathway, which suggests this drug has a favorable modulation on the function of human first-trimester trophoblast cells.


Subject(s)
Cyclosporine/pharmacology , Extracellular Signal-Regulated MAP Kinases/physiology , Matrix Metalloproteinase 2/biosynthesis , Matrix Metalloproteinase 9/biosynthesis , Trophoblasts/physiology , Female , Humans , Mitogen-Activated Protein Kinase 1/physiology , Mitogen-Activated Protein Kinase 3/physiology , Pregnancy , Pregnancy Trimester, First , RNA, Messenger/metabolism , Trophoblasts/drug effects , Up-Regulation
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