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1.
BMC Public Health ; 24(1): 1309, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38745323

ABSTRACT

BACKGROUND: The National Drug Price Negotiation (NDPN) policy has entered a normalisation stage, aiming to alleviate, to some extent, the disease-related and economic burdens experienced by cancer patients. This study analysed the use and subsequent burden of anticancer medicines among cancer patients in a first-tier city in northeast China. METHODS: We assessed the usage of 64 negotiated anticancer medicines using the data on the actual drug deployment situation, the frequency of medical insurance claims and actual medication costs. The affordability of these medicines was measured using the catastrophic health expenditure (CHE) incidence and intensity of occurrence. Finally, we used the defined daily doses (DDDs) and defined daily doses cost (DDDc) as indicators to evaluate the actual use of these medicines in the region. RESULTS: During the study period, 63 of the 64 medicines were readily available. From the perspective of drug usage, the frequency of medical insurance claims for negotiated anticancer medicines and medication costs showed an increasing trend from 2018 to 2021. Cancer patients typically sought medical treatment at tertiary hospitals and purchased medicines at community pharmacies. The overall quantity and cost of medications for patients covered by the Urban Employee Basic Medical Insurance (UEBMI) were five times higher than those covered by the Urban and Rural Resident Medical Insurance (URRMI). The frequency of medical insurance claims and medication costs were highest for lung and breast cancer patients. Furthermore, from 2018 to 2021, CHE incidence showed a decreasing trend (2.85-1.60%) under urban patients' payment capability level, but an increasing trend (11.94%-18.42) under rural patients' payment capability level. The average occurrence intensities for urban (0.55-1.26 times) and rural (1.27-1.74 times) patients showed an increasing trend. From the perspective of drug utilisation, the overall DDD of negotiated anticancer medicines showed an increasing trend, while the DDDc exhibited a decreasing trend. CONCLUSION: This study demonstrates that access to drugs for urban cancer patients has improved. However, patients' medical behaviours are affected by some factors such as hospital level and type of medical insurance. In the future, the Chinese Department of Health Insurance Management should further improve its work in promoting the fairness of medical resource distribution and strengthen its supervision of the nation's health insurance funds.


Subject(s)
Antineoplastic Agents , Drug Costs , Insurance, Health , Humans , China , Antineoplastic Agents/economics , Antineoplastic Agents/therapeutic use , Drug Costs/statistics & numerical data , Insurance, Health/economics , Insurance, Health/statistics & numerical data , Neoplasms/drug therapy , Neoplasms/economics , Female , Male , Negotiating , Health Expenditures/statistics & numerical data , Middle Aged
2.
Front Microbiol ; 13: 852342, 2022.
Article in English | MEDLINE | ID: mdl-35369467

ABSTRACT

The practice of intercropping, which involves growing more than one crop simultaneously during the same growing season, is becoming more important for increasing soil quality, land-use efficiency, and subsequently crop productivity. The present study examined changes in soil physicochemical properties, enzymatic activity, and microbial community composition when walnut (Juglans spp.) was intercropped with tea (Camellia sinensis L.) plants in a forest and compared with a walnut and tea monocropping system. The results showed that walnut-tea intercropping improved the soil nutrient profile and enzymatic activity. The soil available nitrogen (AN), available phosphorus (AP), available potassium (AK), organic matter (OM) content, and sucrase activity were significantly boosted in intercropped walnut and tea than in monocropping forests. The interaction between crops further increased bacterial and fungal diversity when compared to monoculture tea forests. Proteobacteria, Bacteroidetes, Firmicutes, Chlamydiae, Rozellomycota, and Zoopagomycota were found in greater abundance in an intercropping pattern than in monoculture walnut and tea forest plantations. The walnut-tea intercropping system also markedly impacted the abundance of several bacterial and fungal operational taxonomic units (OTUs), which were previously shown to support nutrient cycling, prevent diseases, and ameliorate abiotic stress. The results of this study suggest that intercropping walnut with tea increased host fitness and growth by positively influencing soil microbial populations.

3.
J Anal Test ; 6(3): 247-273, 2022.
Article in English | MEDLINE | ID: mdl-35039787

ABSTRACT

Point-of-care testing (POCT), as a portable and user-friendly technology, can obtain accurate test results immediately at the sampling point. Nowadays, microfluidic paper-based analysis devices (µPads) have attracted the eye of the public and accelerated the development of POCT. A variety of detection methods are combined with µPads to realize precise, rapid and sensitive POCT. This article mainly introduced the development of electrochemistry and optical detection methods on µPads for POCT and their applications on disease analysis, environmental monitoring and food control in the past 5 years. Finally, the challenges and future development prospects of µPads for POCT were discussed.

4.
Pharmazie ; 76(8): 364-371, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34412735

ABSTRACT

At present, how to increase insulin rapidly, availably and stably is still a conundrum in the treatment of diabetes mellitus. In vitro studies have shown that insulin can be released from hydrogel-nanogel composite according to the changes of glucose level. This study aimed to observe the glucose-lowering effects and evaluate the safety of the insulin-loaded hydrogel-nanogel composite in diabetic rats. We found that significant glycemic regulation could be observed up to 30 hours after subcutaneous injection, and the fasting blood glucose was reduced effectively. The result of an oral glucose tolerance test showed that the level of insulin expressed a stable increase from 0.5 hours to 3.5 hours, which led to a reduction of glucose with steady steps. Also, compared with Ins group, the Gel+Ins group showed slighter skin and pancreas damage, while the oxidative stress and inflammation response were similar to the normal control group. In conclusion, these results demonstrated that the glucose-lowering action of the insulin-loaded hydrogel-nanogel composite was superior to that of the regular insulin, and might thus become an insulin carrier in the future.


Subject(s)
Diabetes Mellitus, Experimental , Insulin , Animals , Blood Glucose , Hydrogels/adverse effects , Hypoglycemic Agents/pharmacology , Nanogels , Rats , Streptozocin/adverse effects
5.
J Cell Mol Med ; 25(11): 4938-4949, 2021 06.
Article in English | MEDLINE | ID: mdl-33939251

ABSTRACT

Drug-mediated or medical condition-mediated disruption of hERG function accounts for the main cause of acquired long-QT syndrome (acLQTs), which predisposes affected individuals to ventricular arrhythmias (VA) and sudden death. Many Chinese herbal medicines, especially alkaloids, have risks of arrhythmia in clinical application. The characterized mechanisms behind this adverse effect are frequently associated with inhibition of cardiac hERG channels. The present study aimed to assess the potent effect of Rutaecarpine (Rut) on hERG channels. hERG-HEK293 cell was applied for evaluating the effect of Rut on hERG channels and the underlying mechanism. hERG current (IhERG ) was measured by patch-clamp technique. Protein levels were analysed by Western blot, and the phosphorylation of Sp1 was determined by immunoprecipitation. Optical mapping and programmed electrical stimulation were used to evaluate cardiac electrophysiological activities, such as APD, QT/QTc, occurrence of arrhythmia, phase singularities (PSs), and dominant frequency (DF). Our results demonstrated that Rut reduced the IhERG by binding to F656 and Y652 amino acid residues of hERG channel instantaneously, subsequently accelerating the channel inactivation, and being trapped in the channel. The level of hERG channels was reduced by incubating with Rut for 24 hours, and Sp1 in nucleus was inhibited simultaneously. Mechanismly, Rut reduced threonine (Thr)/ tyrosine (Tyr) phosphorylation of Sp1 through PI3K/Akt pathway to regulate hERG channels expression. Cell-based model unables to fully reveal the pathological process of arrhythmia. In vivo study, we found that Rut prolonged QT/QTc intervals and increased induction rate of ventricular fibrillation (VF) in guinea pig heart after being dosed Rut for 2 weeks. The critical reasons led to increased incidence of arrhythmias eventually were prolonged APD90 and APD50 and the increase of DF, numbers of PSs, incidence of early after-depolarizations (EADs). Collectively, the results of this study suggest that Rut could reduce the IhERG by binding to hERG channels through F656 and Y652 instantaneously. While, the PI3K/Akt/Sp1 axis may play an essential role in the regulation of hERG channels, from the perspective of the long-term effects of Rut (incubating for 24 hours). Importantly, the changes of electrophysiological properties by Rut were the main cause of VA.


Subject(s)
Action Potentials , Arrhythmias, Cardiac/pathology , ERG1 Potassium Channel/antagonists & inhibitors , Indole Alkaloids/adverse effects , Long QT Syndrome/pathology , Quinazolines/adverse effects , Vasodilator Agents/adverse effects , Ventricular Dysfunction/pathology , Animals , Arrhythmias, Cardiac/chemically induced , Arrhythmias, Cardiac/metabolism , Cells, Cultured , Electrophysiological Phenomena , Guinea Pigs , HEK293 Cells , Humans , Long QT Syndrome/chemically induced , Long QT Syndrome/metabolism , Male , Ventricular Dysfunction/chemically induced , Ventricular Dysfunction/metabolism
6.
Curr Pharm Des ; 25(43): 4606-4612, 2020.
Article in English | MEDLINE | ID: mdl-31657676

ABSTRACT

BACKGROUND: The human ether-a-go-go-related gene (hERG) potassium channel is the rapidly activating component of cardiac delayed rectifier potassium current (IKr), which is a crucial determinant of cardiac repolarization. The reduction of hERG current is commonly believed to cause Long QT Syndrome (LQTs). Probucol, a cholesterol-lowering drug, induces LQTs by inhibiting the expression of the hERG channel. Unfortunately, there is currently no effective therapeutic method to rescue probucol-induced LQTs. METHODS: Patch-clamp recording techniques were used to detect the action potential duration (APD) and current of hERG. Western blot was performed to measure the expression levels of proteins. RESULTS: In this study, we demonstrated that 1 µM matrine and oxymatrine could rescue the hERG current and hERG surface expression inhibited by probucol. In addition, matrine and oxymatrine significantly shortened the prolonged action potential duration induced by probucol in neonatal cardiac myocytes. We proposed a novel mechanism underlying the probucol induced decrease in the expression of transcription factor Specificity protein 1 (Sp1), which is an established transactivator of the hERG gene. We also demonstrated that matrine and oxymatrine were able to upregulate Sp1 expression which may be one of the possible mechanisms by which matrine and oxymatrine rescued probucol-induced hERG channel deficiency. CONCLUSION: Our current results demonstrate that matrine and oxymatrine could rescue probucol-induced hERG deficiency in vitro, which may lead to potentially effective therapeutic drugs for treating acquired LQT2 by probucol in the future.


Subject(s)
Alkaloids/pharmacology , Ether-A-Go-Go Potassium Channels/antagonists & inhibitors , Myocytes, Cardiac/drug effects , Probucol/adverse effects , Quinolizines/pharmacology , Animals , Cell Line , Humans , Patch-Clamp Techniques , Rats, Sprague-Dawley , Matrines
7.
Mol Pharm ; 16(4): 1477-1488, 2019 04 01.
Article in English | MEDLINE | ID: mdl-30807184

ABSTRACT

The hERG potassium channel (IKr) encoded by human ether-a-go-go-related gene plays an important role in cardiac repolarization. Decreased IKr may lead to long QT syndrome, which subsequently causes torsade de pointes and sudden cardiac death. Previous studies have shown that statins inhibit IKr and are more potent in inhibiting hERG currents when combined with other drugs. Since chemical structure of rosuvastatin is similar to that of several IKr blockers (ibutilide and E-4031), the present study aimed to reveal the mechanism that underlies rosuvastatin-induced hERG current reduction and to evaluate the possibility of cardiac toxicity. The results showed that rosuvastatin reduced hERG currents by accelerating the inactivation and prolonged action potential duration (APD) in hiPSC-CMs. Meanwhile, it was observed that rosuvastatin reduced the expression of the mature hERG. Transcription factor Sp1 was involved in hERG protein downregulation induced by rosuvastatin, and the result was verified by Sp1 siRNA and Sp1 agonist epicatechin. These results indicated that rosuvastatin could potentially inhibit transcription and reduce hERG mRNA expression. The interaction between hERG and heat shock protein was evaluated to study the mechanism of trafficking inhibition through co-immunoprecipitation. We found that rosuvastatin reduces the interaction of heat shock protein 70 (Hsp70) with the hERG protein, thereby affecting the folding of the hERG channel. Additionally, rosuvastatin significantly activates ATF6, which plays a key role in the activation of the unfolded protein response (UPR) pathway. Increased expression of the molecular chaperone calnexin and calreticulin, which are activated by ATF6 to help channel folding, further confirmed UPR activation. Meanwhile, the degradation of the hERG channel was mediated by lysosomes and proteasomes. In conclusion, Rosuvastatin reduced the expression of hERG plasma membrane by two pathways, the first is to disrupt the transport of immature hERG channels to the membrane, and the second is to increase the degradation of mature hERG channels. In addition, Rosuvastatin potently blocked hERG current, delayed cardiac repolarization, and thereby prolonged APDs and QTc intervals. Therefore, caution should be taken when rosuvastatin is used in the treatment of hyperlipidemia, especially when combined with drugs that can prolong the QT interval.


Subject(s)
Anticholesteremic Agents/pharmacology , Cell Membrane/metabolism , Ether-A-Go-Go Potassium Channels/metabolism , Induced Pluripotent Stem Cells/metabolism , Myocytes, Cardiac/metabolism , Proteolysis/drug effects , Rosuvastatin Calcium/pharmacology , Action Potentials , Cell Membrane/drug effects , Ether-A-Go-Go Potassium Channels/drug effects , HEK293 Cells , Humans , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/drug effects , Myocytes, Cardiac/cytology , Myocytes, Cardiac/drug effects , Protein Transport , Unfolded Protein Response
8.
Biomed Environ Sci ; 31(7): 507-514, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30145985

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the ability of Pref-1+ adipocyte progenitor cells to mobilize into mesenteric lymph nodes (MLNs) and the dynamic expression of related chemokines during the development of rat MLNs. METHODS: Immunohistochemical analyses were used to detect the expression of Pref-1 and related chemokines. Transmission electron microscopy (TEM) was used to observe the changes in ultrastructure of MLNs. RESULTS: Cells containing lipid droplets were found in all rat MLNs at embryonic day (E) 18.5, 2 and 6 weeks (w) after birth, and they were similar to fibroblastic reticular cells (FRCs) or follicular dendritic cells (FDCs) under TEM. Pref-1+ adipocyte progenitor cells were found in all MLNs. The expression level of Pref-1 was significantly increased at 2 w after birth and decreased at 6 w after birth. The tendency of Cxcl12 expression was consistent with that of Pref-1 and was positively correlated with the expression of Pref-1 (P < 0.01; r = 0.897). At E18.5, Cxcl13, and Ccr7 were significantly expressed in the MLN anlage, but the expression level of Ccl21 was low. The expression level of Cxcl13, Ccr7, and Ccl21 in MLN were significantly increased at 2 w after birth (P < 0.05), while the expression of Ccr7 and Ccl21 were significantly decreased at 6 w after birth (P < 0.05). CONCLUSION: Adipocyte progenitor cells are involved in the rat MLNs development through differentiation into FRC and FDC. The expression of the relevant chemokines during the development of MLNs is dynamic and may be related to the maintenance of lymph nodes self-balance state.


Subject(s)
Chemokines/metabolism , Gene Expression Regulation, Developmental/physiology , Intercellular Signaling Peptides and Proteins/metabolism , Lymph Nodes/metabolism , Membrane Proteins/metabolism , Mesentery/embryology , Animals , Chemokines/genetics , Female , Intercellular Signaling Peptides and Proteins/genetics , Lymph Nodes/embryology , Membrane Proteins/genetics , Pregnancy , Rats
9.
Tumour Biol ; 37(3): 3675-81, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26462837

ABSTRACT

Liver cancer is one of the most common human malignancies, and transforming growth factor-beta (TGF-ß) pathway plays a key role in its pathogenesis. To study the relationship between TGF-ß pathway and the related protein expression of many signaling pathway, markers of stem cells, CK family, and others, liver cancer HepG2 cells were transfected with siRNA directed against TGF-ß1 or were treated with exogenous TGF-ß1. Then, these protein levels were measured by Western blotting. After siRNA transfection, TGF-ß1 protein level was decreased, indicating that the siRNA against it was effective. In exogenous TGF-ß1 group, the expression of smad4, smad2/3, and ß-catenin proteins was increased, whereas that of p-smad2/3, CD133, cleaved Notch1, and epithelial cell adhesion molecule (EpCAM) proteins at 48 h was decreased. The expression of CK8 and CK18 proteins was increased at 24 h and was decreased at 48 and 96 h. In TGF-ß1-silenced group, the expression of smad2/3, ß-catenin, cleaved-notch1, and CK18 proteins was decreased, while that of smad4, p-smad2/3, CD133, EpCAM, and CK8 proteins was increased. TERT protein expression was slightly increased in exogenous TGF-ß1 group at 48 h and in TGF-ß1-silenced group at 96 h. TGF-ß1 did not affect the protein expression of CK19 and HIF-1. Thus, TGF-ß1 pathway plays an important role in cell regulation of liver cancer through the modulation of these proteins. These data will contribute to the understanding of the pathogenesis of liver cancer and the role of TGF-ß pathway in this process.


Subject(s)
Biomarkers, Tumor/metabolism , Keratins/metabolism , Neoplastic Stem Cells/metabolism , Signal Transduction , Telomerase/metabolism , Transforming Growth Factor beta1/metabolism , AC133 Antigen/metabolism , Blotting, Western , Epithelial Cell Adhesion Molecule/metabolism , Hep G2 Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit , Keratin-18/metabolism , Keratin-8/metabolism , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/pathology , RNA Interference , Smad Proteins/metabolism , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/pharmacology , beta Catenin/metabolism
10.
Oncol Lett ; 12(6): 4961-4968, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28105202

ABSTRACT

Urotensin II (UII) and the urotensin II receptor (UT) exhibit mitogenic effects on tumor growth. Our previous study demonstrated that the UII/UT system is upregulated in hepatocellular carcinoma (HCC) and may enhance the proliferation of human hepatoma cells. However, the clinical significance of UII/UT expression in HCC remains unclear. The present study assessed UII messenger RNA (mRNA) expression in 129 surgical specimens obtained from HCC patients using reverse transcription quantitative-polymerase chain reaction. The association between UII mRNA expression and clinicopathological parameters and overall survival rates was also investigated. The results revealed that UII and UT mRNA expression was significantly increased in HCC tissue compared with adjacent non-cancerous liver tissue (P<0.001). Furthermore, a significant correlation was identified between UII expression and histological differentiation (P<0.01), tumor size (P<0.01) and tumor stage (P=0.026). Kaplan-Meier survival analysis indicated that overall survival time was significantly shorter in patients with high UII expression, compared with those with low UII expression (P<0.001). Multivariate analyses indicated that UII expression was an independent predictor of overall survival (odds ratio, 1.12; P<0.001). In addition, UII mRNA was correlated with vascular endothelial growth factor mRNA expression. Therefore, UII expression is an independent biomarker for the prognosis of patients with HCC and thus, the UII/UT system may present a novel therapeutic target for the treatment of HCC.

11.
Drug Des Devel Ther ; 9: 3695-704, 2015.
Article in English | MEDLINE | ID: mdl-26229434

ABSTRACT

The hERG gene encodes the pore-forming α-subunit of the rapidly activating delayed rectifier potassium channel (I Kr), which is important for cardiac repolarization. Reduction of I hERG due to genetic mutations or drug interferences causes long QT syndrome, leading to life-threatening cardiac arrhythmias (torsades de pointes) or sudden death. Probucol is a cholesterol-lowering drug that could reduce hERG current by decreasing plasma membrane hERG protein expression and eventually cause long QT syndrome. Here, we investigated the mechanisms of probucol effects on I hERG and hERG-channel expression. Our data demonstrated that probucol reduces SGK1 expression, known as SGK isoform, in a concentration-dependent manner, resulting in downregulation of phosphorylated E3 ubiquitin ligase Nedd4-2 expression, but not the total level of Nedd4-2. As a result, the hERG protein reduces, due to the enhanced ubiquitination level. On the contrary, carbachol could enhance the phosphorylation level of Nedd4-2 as an alternative to SGK1, and thus rescue the ubiquitin-mediated degradation of hERG channels caused by probucol. These discoveries provide a novel mechanism of probucol-induced hERG-channel deficiency, and imply that carbachol or its analog may serve as potential therapeutic compounds for the handling of probucol cardiotoxicity.


Subject(s)
Anticholesteremic Agents/toxicity , Ether-A-Go-Go Potassium Channels/genetics , Long QT Syndrome/chemically induced , Probucol/toxicity , Anticholesteremic Agents/administration & dosage , Carbachol/pharmacology , Dose-Response Relationship, Drug , ERG1 Potassium Channel , Endosomal Sorting Complexes Required for Transport/metabolism , HEK293 Cells , Humans , Immediate-Early Proteins/genetics , Nedd4 Ubiquitin Protein Ligases , Phosphorylation/drug effects , Probucol/administration & dosage , Protein Serine-Threonine Kinases/genetics , Ubiquitin-Protein Ligases/metabolism
12.
Cell Physiol Biochem ; 37(1): 284-96, 2015.
Article in English | MEDLINE | ID: mdl-26303164

ABSTRACT

BACKGROUND/AIMS: Abnormal QT prolongation is the most prominent cardiac electrical disturbance in patients with diabetes mellitus (DM). It is well known that the human ether-ago-go-related gene (hERG) controls the rapid delayed rectifier K+ current (IKr) in cardiac cells. The expression of the hERG channel is severely down-regulated in diabetic hearts, and this down-regulation is a critical contributor to the slowing of repolarization and QT prolongation. However, the intracellular mechanisms underlying the diabetes-induced hERG deficiency remain unknown. METHODS: The expression of the hERG channel was assessed via western blot analysis, and the hERG current was detected with a patch-clamp technique. RESULTS: The results of our study revealed that the expression of the hERG protein and the hERG current were substantially decreased in high-glucose-treated hERG-HEK cells. Moreover, we demonstrated that the high-glucose-mediated damage to the hERG channel depended on the down-regulation of protein levels but not the alteration of channel kinetics. These discoveries indicated that high glucose likely disrupted hERG channel trafficking. From the western blot and immunoprecipitation analyses, we found that high glucose induced trafficking inhibition through an effect on the expression of Hsp90 and its interaction with hERG. Furthermore, the high-glucose-induced inhibition of hERG channel trafficking could activate the unfolded protein response (UPR) by up-regulating the expression levels of activating transcription factor-6 (ATF-6) and the ER chaperone protein calnexin. In addition, we demonstrated that 100 nM insulin up-regulated the expression of the hERG channel and rescued the hERG channel repression caused by high glucose. CONCLUSION: The results of our study provide the first evidence of a high-glucose-induced hERG channel deficiency resulting from the inhibition of channel trafficking. Furthermore, insulin promotes the expression of the hERG channel and ameliorates the high-glucose-induced inhibition of the hERG channel.


Subject(s)
Ether-A-Go-Go Potassium Channels/metabolism , Glucose/metabolism , Protein Transport/physiology , Action Potentials/physiology , Arrhythmias, Cardiac/metabolism , Brugada Syndrome , Cardiac Conduction System Disease , Cell Line , Down-Regulation/physiology , Gene Expression/physiology , HEK293 Cells , HSP90 Heat-Shock Proteins/metabolism , Heart Conduction System/abnormalities , Heart Conduction System/metabolism , Humans , Insulin/metabolism , Myocytes, Cardiac/metabolism , Patch-Clamp Techniques/methods , Up-Regulation/physiology
13.
Eur J Pharm Sci ; 76: 149-55, 2015 Aug 30.
Article in English | MEDLINE | ID: mdl-25976224

ABSTRACT

As is well-known, hERG plays an essential role in phase III repolarization of cardiac action potentials. Blocking of hERG channels can lead to LQTS. Inhibition of the metabolism of CYPs activities may elevate plasma levels, to further increase accumulation of drug on cardiac. The elevated serum levels may however elicit unexpected toxicities. Therefore, the inhibition tests of hERG and CYP are central to the preclinical studies because they may lead to severe cardiac toxicity. Berberine is widely used as an antibacterial agent and often combined with macrolides to treat gastropathy. Our objective was to assess cardiac toxicity during the combined use of Berberine with macrolides. (1) Azithromycin reduced hERG currents by accelerated channel inactivation. (2) The combination of Berberine with Azithromycin reduced hERG currents, producing an inhibitive effect stronger than use of a single drug alone, due to the high binding affinity for the onset of inactivation. (3) When cells were perfused concomitantly with Berberine and Clarithromycin, they showed a stronger inhibitive effect on hERG currents by decreasing the time constant for the onset of inactivation. (4) The combined administration of Berberine with Clarithromycin had a powerful inhibitive effect on CYP3A activities than use of a single drug alone. Collectively, these results demonstrated that concomitant use of Berberine with macrolides may require close monitoring because of potential drug toxicities, especially cardiac toxicity.


Subject(s)
Anti-Bacterial Agents/toxicity , Azithromycin/toxicity , Berberine/toxicity , Clarithromycin/toxicity , Cytochrome P-450 CYP3A Inhibitors/toxicity , Ether-A-Go-Go Potassium Channels/antagonists & inhibitors , Heart Diseases/chemically induced , Myocytes, Cardiac/drug effects , Potassium Channel Blockers/toxicity , Animals , Cytochrome P-450 CYP3A/metabolism , Drug Synergism , ERG1 Potassium Channel , Ether-A-Go-Go Potassium Channels/genetics , Ether-A-Go-Go Potassium Channels/metabolism , HEK293 Cells , Heart Diseases/metabolism , Heart Diseases/physiopathology , Humans , Male , Membrane Potentials , Microsomes, Liver/enzymology , Myocytes, Cardiac/metabolism , Rats , Rats, Wistar , Risk Assessment , Transfection
14.
Basic Clin Pharmacol Toxicol ; 116(6): 516-23, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25395240

ABSTRACT

Arsenic trioxide (As2O3) is used to treat acute pro-myelocytic leukaemia. However, the cardiotoxicity of long QT syndrome restricts its clinical application. Previous studies showed that As2O3 can damage the hERG current via disturbing its trafficking to cellular membrane. Consistent with these findings, in this study, we reported that As2O3 inhibited hERG channel at both protein and mRNA levels and damaged hERG current but did not affect channel kinetics. Further, we demonstrated that As2O3 up-regulated miR-21 and miR-23a expression in hERG-HEK293 cells and neonatal cardiomyocytes. In addition, knock-down of miR-21 by its specific antisense molecules AMO-21 was able to rescue Sp1 and hERG inhibition caused by As2O3. Consistently, phosphorylation of NF-κB, the upstream regulatory factor of miR-21, was significantly up-regulated by As2O3 . This finding revealed that regulation of the NF-κB-miR-21-Sp1 signalling pathway is a novel mechanism for As2O3-induced hERG inhibition. Meanwhile, the expression of Hsp90 and hERG was rescued by transfection with AMO-23a. And the hERG channel inhibition induced by As2O3 was rescued after being transfected with AMO-23a, which may be a molecular mechanism for the role of As2O3 in hERG trafficking deficiency. In brief, our study revealed that miR-21 and miR-23a are involved in As2O3-induced hERG deficiency at transcriptional and transportational levels. This discovery may provide a novel mechanism of As2O3-induced hERG channel deficiency, and these miRNAs may serve as potential therapeutic targets for the handling of As2O3 cardiotoxicity.


Subject(s)
Ether-A-Go-Go Potassium Channels/deficiency , MicroRNAs/biosynthesis , Oxides/toxicity , Potassium Channel Blockers/toxicity , Animals , Animals, Newborn , Arsenic Trioxide , Arsenicals , Ether-A-Go-Go Potassium Channels/drug effects , In Vitro Techniques , Kinetics , MicroRNAs/drug effects , Myocytes, Cardiac/drug effects , NF-kappa B/metabolism , Phosphorylation , Rats , Rats, Sprague-Dawley , Transfection , Up-Regulation/drug effects
15.
Huan Jing Ke Xue ; 35(9): 3256-62, 2014 Sep.
Article in Chinese | MEDLINE | ID: mdl-25518639

ABSTRACT

In this paper, the continuous (2009-2010) measurement of atmospheric CO2 and CH4 from the Mount Waliguan Baseline Observatory of Western China are presented. The results show that about 17% of CO2 observations are classified as polluted due to more frequently influence of regional emission on local measurement in summer time. The mean concentration of CO2 measured at the period of 2009 to 2010 was 390.72 x 10(-6) which was 17.4 x 10(-6) higher than that measured from 1995 to 2008, and the median concentration of CH4 was 1851.11 x 10(-9) which was 16 x 10(-9) higher than that from 2002 to 2006, which implied that the regional emission of CO2 and CH4 was continuously increased. The unavailable data were filled by back propagation neural network (BPNN) and optimized by genetic algorithm (GA) , which were analyzed by the Fourier analysis of time series of air temperature, wind speed, concentration of CO2 and CH4. At the daily time scale, strong spectrum peak occurred and concentration recorded at periods of 12 and 24 hours,due to the daily sun activity changes. At the monthly time scale, the spectrum gap occurred in CO2 concentration at periods of 30 day suggesting that the effect of meteorological and phenological factors on the variation of CO2 concentration was insignificant.


Subject(s)
Air Pollutants/analysis , Carbon Dioxide/analysis , Environmental Monitoring , Methane/analysis , China , Seasons , Temperature , Wind
16.
Acta Pharmacol Sin ; 35(12): 1473-84, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25418379

ABSTRACT

The human ether-à-go-go related gene (hERG) potassium channel is an obligatory anti-target for drug development on account of its essential role in cardiac repolarization and its close association with arrhythmia. Diverse drugs have been removed from the market owing to their inhibitory activity on the hERG channel and their contribution to acquired long QT syndrome (LQTS). Moreover, mutations that cause hERG channel dysfunction may induce congenital LQTS. Recently, an increasing number of biochemical and molecular mechanisms underlying hERG-associated LQTS have been reported. In fact, numerous potential biochemical and molecular rescue strategies are hidden within the biogenesis and regulating network. So far, rescue strategies of hERG channel dysfunction and LQTS mainly include activators, blockers, and molecules that interfere with specific links and other mechanisms. The aim of this review is to discuss the rescue strategies based on hERG channel toxicology from the biochemical and molecular perspectives.


Subject(s)
Ether-A-Go-Go Potassium Channels/drug effects , Long QT Syndrome/drug therapy , Toxicology , Translational Research, Biomedical , Animals , ERG1 Potassium Channel , Ether-A-Go-Go Potassium Channels/genetics , Ether-A-Go-Go Potassium Channels/metabolism , Gene Expression Regulation , Genetic Predisposition to Disease , Humans , Long QT Syndrome/chemically induced , Long QT Syndrome/genetics , Long QT Syndrome/metabolism , Long QT Syndrome/physiopathology , Mutation , Phenotype , Protein Transport , Risk Assessment , Signal Transduction/drug effects
17.
Naunyn Schmiedebergs Arch Pharmacol ; 387(11): 1079-89, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25107562

ABSTRACT

Arsenic trioxide (As2O3) is used to treat acute promyelocytic leukemia. However, the cardiotoxicity of long QT syndrome restricts its clinical application. Previous studies showed that As2O3 can damage the human ether-a-go-go-related gene (hERG) current via disturbing its trafficking to cellular membrane. This study aimed to investigate whether the As2O3-insulted hERG channel can be rescued by resveratrol, a recognized cardioprotective agent. The whole-cell patch clamp technique was used to record the hERG current and action potential duration. Co-immunoprecipitation and Western blot assay were applied to determine the function of hERG-Hsp70/Hsp90 chaperone complexes and the expression alteration of protein-folding-related proteins, respectively. Compared with treatment of As2O3 alone, co-treatment with resveratrol successfully restored the current and surface expression of hERG and obviously shortened action potential duration in guinea pig ventricular myocytes. Further experiments demonstrate that resveratrol relieved As2O3-caused endoplasmic reticulum (ER) stress by restoring the function of hERG-Hsp70/Hsp90 chaperone complexes and downregulating the protein expression of ER chaperone proteins (calnexin and calreticulin) and activating transcription factor 6. In conclusion, resveratrol was able to rescue the trafficking deficiency and relieve the ER stress (ERS). Our findings suggest that resveratrol has a potential effect to alleviate the adverse effect of As2O3 on cardiotoxicity.


Subject(s)
Cardiotoxicity/prevention & control , Endoplasmic Reticulum Stress/drug effects , Oxides/toxicity , Stilbenes/pharmacology , Action Potentials/drug effects , Animals , Antineoplastic Agents/toxicity , Arsenic Trioxide , Arsenicals , Blotting, Western , Cardiotonic Agents/pharmacology , Cardiotoxicity/etiology , Down-Regulation/drug effects , ERG1 Potassium Channel , Ether-A-Go-Go Potassium Channels/deficiency , Guinea Pigs , HEK293 Cells , HSP70 Heat-Shock Proteins/metabolism , HSP90 Heat-Shock Proteins/metabolism , Heart Ventricles/drug effects , Heart Ventricles/metabolism , Humans , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Patch-Clamp Techniques , Resveratrol
18.
Exp Biol Med (Maywood) ; 239(8): 998-1006, 2014 08.
Article in English | MEDLINE | ID: mdl-24872431

ABSTRACT

Decreasing hepatic fibrosis remains one of the major therapeutic challenges in hepatology. The present study aims to evaluate the effect of Endostar on both CCl4-induced liver fibrosis in mice and a hepatic stellate cell (HSC) line. Two main models were studied: (i) a liver fibrosis model was induced in BALB/c mice using CCl4 by intraperitoneal injection for six weeks. Six animal groups were studied: group 1: normal animals; group 2: CCl4-induced liver fibrosis; group 3: CCl4 + Endostar 20 mg/kg/d, six weeks; group 4: CCl4 + Endostar 10 mg/kg/d, six weeks; group 5: CCl4 + Endostar 20 mg/kg/d, four weeks; group 6: CCl4 + Endostar 10 mg/kg/d, four weeks corresponded to different Endostar doses and duration of administration. Liver fibrosis was evaluated by histopathological staining and liver hydroxyproline content. Expressions of collagen type I, α-smooth muscle actin (α-SMA), TGF-ß1 and VEGFR were measured by real-time polymerase chain reaction (PCR). (ii) A liver cell model. HSC-T6 cells were cultured with or without Endostar for 12 h or 24 h. Expressions of collagen type I, α-SMA, and TGF-ß1 were measured by real-time PCR. Collagen I and transforming growth factor ß1 (TGF-ß1) contents in cell supernatant were measured by enzyme-linked immunosorbent assay. As compared to the group without Endostar, liver fibrosis scores and hydroxyproline content were decreased in both Endostar groups (P < 0.05). Moreover, Endostar inhibited the hepatic expression of α-SMA, TGF-ß1, Collagen-1, VEGFR1, and VEGFR2 mRNA (P < 0.05). In the HSC-T6 cell line model, Endostar profoundly inhibited the expression of α-SMA, Collagen-1, and TGF-ß1 mRNA. Expressions of Collagen-1 and TGF-ß1 protein were decreased in the Endostar group as compared to the normal controls in the supernatant of HSC-T6 cells (P < 0.05). Endostar decreased both liver fibrosis in CCl4-induced mice and collagen synthesis in HSCs in vitro. Therefore, this recombinant human endostatin is a promising compound for counteracting liver fibrosis.

19.
J Pharmacol Sci ; 123(4): 318-27, 2013.
Article in English | MEDLINE | ID: mdl-24225402

ABSTRACT

We investigated the effects of Ginkgo biloba extract (GBE) and ginkgolide (GLD) on human ether-a-go-go-related gene (hERG)-encoded K(+) channels and its underlying mechanisms in the hERG-HEK293 cell line by determining GBE- and GLD-induced changes in action potential duration (APD), L-type calcium currents (ICa-L), and the intracellular calcium concentration ([Ca(2+)]i) in guinea-pig ventricular myocytes. hERG currents, APD and ICa-L were recorded using the whole-cell patch clamp technique, the [Ca(2+)]i was examined by an immunofluorescence experiment. In the present study, we found that a low concentration of GBE (0.005 mg/ml) increased hERG currents, but the high concentration of GBE (from 0.05 to 0.25 mg/ml) reduced hERG currents. GLD reduced hERG currents in a concentration-dependent manner (from 0.005 to 0.25 mg/ml). Both GBE and GLD altered kinetics of the hERG channel. GBE accelerated the activation of hERG channels without changing the inactivation curve, but reduced the time constant of inactivation; GLD did not shift the activation or the inactivation curve, but only reduced the time constant of inactivation. Both GBE and GLD shortened the APD, inhibited the ICa-L currents, and decreased the [Ca(2+)]i in isolated guinea-pig ventricular myocytes. The results indicate that GBE and GLD can prevent ischemic arrhythmias and have an antiarrhythmic effect potential via inhibition of IKr and ICa-L currents.


Subject(s)
Anti-Arrhythmia Agents , Ether-A-Go-Go Potassium Channels/genetics , Ginkgo biloba , Ginkgolides/pharmacology , Plant Extracts/pharmacology , Action Potentials/drug effects , Animals , Arrhythmias, Cardiac/prevention & control , Calcium/metabolism , Cells, Cultured , Dose-Response Relationship, Drug , Guinea Pigs , HEK293 Cells , Heart Ventricles , Humans , Molecular Targeted Therapy , Myocytes, Cardiac/metabolism , Phytotherapy
20.
Clin Imaging ; 37(1): 159-62, 2013.
Article in English | MEDLINE | ID: mdl-23206625

ABSTRACT

Pulmonary embolism is the most frequent diagnosis for a filling defect in the pulmonary artery, but a tumor in the arteriae pulmonalis should be contained in the differential diagnosis. Primary pulmonary artery myxoma is extremely rare, and only a few cases have been reported. The early diagnosis of this disease is difficult, but it is feasible with modern radiographic methods, which play an important role in the presentation of the origin and extension of the tumor. Here, we review one case with computed tomographic (CT) and pulmonary CT angiographic findings to emphasize the significance of the imaging method in its diagnosis.


Subject(s)
Angiography/methods , Myxoma/diagnostic imaging , Pulmonary Artery/diagnostic imaging , Tomography, X-Ray Computed/methods , Vascular Neoplasms/diagnostic imaging , Female , Humans , Middle Aged , Rare Diseases/diagnostic imaging
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