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Zhang X, An H, Li J, Zhang Y, Liu Y, Jia Z, Zhang W, Chu L, Zhang H. Selective activation of vascular K v 7.4/K v 7.5 K + channels by fasudil contributes to its vasorelaxant effect. Br J Pharmacol 2016; 173:3480-3491. [PMID: 27677924 DOI: 10.1111/bph.13639] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 09/13/2016] [Accepted: 09/15/2016] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Kv 7 (Kv 7.1-7.5) channels play an important role in the regulation of neuronal excitability and the cardiac action potential. Growing evidence suggests Kv 7.4/Kv 7.5 channels play a crucial role in regulating vascular smooth muscle contractility. Most of the reported Kv 7 openers have shown poor selectivity across these five subtypes. In this study, fasudil - a drug used for cerebral vasospasm - has been found to be a selective opener of Kv 7.4/Kv 7.5 channels. EXPERIMENTAL APPROACH A perforated whole-cell patch technique was used to record the currents and membrane potential. Homology modelling and a docking technique were used to investigate the interaction between fasudil and the Kv 7.4 channel. An isometric tension recording technique was used to assess the vascular tension. KEY RESULTS Fasudil selectively and potently enhanced Kv 7.4 and Kv 7.4/Kv 7.5 currents expressed in HEK293 cells, and shifted the voltage-dependent activation curve in a more negative direction. Fasudil did not affect either Kv 7.2 and Kv 7.2/Kv 7.3 currents expressed in HEK293 cells, the native neuronal M-type K+ currents, or the resting membrane potential in small rat dorsal root ganglia neurons. The Val248 in S5 and Ile308 in S6 segment of Kv 7.4 were critical for this activating effect of fasudil. Fasudil relaxed precontracted rat small arteries in a concentration-dependent fashion; this effect was antagonized by the Kv 7 channel blocker XE991. CONCLUSIONS AND IMPLICATIONS These results suggest that fasudil is a selective Kv 7.4/Kv 7.5 channel opener and provide a new dimension for developing selective Kv 7 modulators and a new prospective for the use, action and mechanism of fasudil.
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Chu L, Zhang J, Li YN, Long DY. [Clinical analysis of 19 cases of pregnant women with rapid arrhythmia in the treatment of radiofrequency catheter ablation]. ZHONGHUA FU CHAN KE ZA ZHI 2016; 51:759-764. [PMID: 27788744 DOI: 10.3760/cma.j.issn.0529-567x.2016.10.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the risk of radiofrequency catheter ablation and maternal and infant in pregnant women with rapid arrhythmia during pregnancy. Methods: The clinical data of the 19 cases of pregnancy complicated with rapid arrhythmia were retrospectively analyzed and followed up, including the gestational week, the type of arrhythmia, the treatment, and the outcome of the mother and child in Beijing Anzhen Hospital of Capital Medical University from January 2002 to March 2016. Results: (1)Clinical characteristics: the ages of the 19 cases were(31±4)years old(ranged from 26 to 35 years old), the onset gestational ages were(21±4)weeks(ranged from 15 to 32 weeks). CLINICAL SYMPTOMS paroxysmal palpitation, chest tightness, dizziness, and blurred vision. Arrhythmia types: 1 case of atrial flutter and atrial tachycardia, 1 case of atrial flutter and atrial fibrillation, 1 case of atrial fibrillation, 3 cases of supraventricular tachycardia, 1 case of atrial tachycardia and supraventricular tachycardia, 4 cases of ventricular tachycardia, 3 cases of ventricular premature beats and ventricular tachycardia, and 5 cases of atrial tachycardia. All cases were treated by drugs, but all failed 2 cases of them were performed esophageal pacing and cardioversion and also failed.(2)Treatment plan: 19 cases after treatment of arrhythmia, completely terminated, the first 7 patients(from 2002 to 2014)were operated in a small amount of radiation under the guidance, the other 12 patients(after 2015)were carried out in the Ensite NavX mapping system, whichwere operated with zero radiation. Complications and adverse reactions: 1 case of uterine contraction end operation and was gived magnesium sulfate 3 days intravenous inhibition of uterine contractions, 1 case occurred vagal reflex caused by reduced blood pressure and was gived fluid infusion utill normal blood pressure.(3)Maternal and neonatal outcomes: in addition 1 case of pregnancy to give up, the remaining 18 cases were full-term pregnant women, including 4 cases of vaginal delivery and 14 cases of cesarean section. The survival neonates were followed up for 1 to 14 years, average(2.0 ± 2.9)years. The infants were well developed during the follow-up period. Conclution: Radiofrequency catheter ablation is a safe and effective method for the treatment of pregnancy complicated with rapid arrhythmia.
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Zhang GH, Cui LJ, Li AY, Zhang JP, Liu Y, Zhao JS, Xu XB, He B, Wang JD, Chu L, Li YF. Endometrial breakdown with sustained progesterone release involves NF-κB-mediated functional progesterone withdrawal in a mouse implant model. Mol Reprod Dev 2016; 83:780-791. [PMID: 27500900 DOI: 10.1002/mrd.22686] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 07/26/2016] [Indexed: 12/23/2022]
Abstract
Irregular uterine bleeding is a major side effect of long-acting progestogen-only contraceptives in women, and is the primary reason women discontinue their use. In this study, a mouse model of endometrial breakdown was established using a subcutaneous progesterone implant to understand how irregular bleeding begins. Although progestogens sustained decidualization, endometrial breakdown was still observed in this model. We, therefore, hypothesized that endometrial breakdown might involve functional progesterone withdrawal. Using co-immunoprecipitation assays, we observed the constitutive activation of nuclear factor kappa-b (NF-κB) p65 and its interaction with the progesterone receptor (PGR); moreover, transcriptional activity of the PGR was also repressed by NF-κB activity in primary mouse and human decidual stromal cells that mimic progesterone maintenance. Yet the ratio of PGR-B to PGR-A was not increased in the mouse model. In vivo comparison of endometrial breakdown induced by progesterone withdrawal to that seen during sustained progesterone exposure, in the presence of NF-κB inhibitors, revealed that NF-κB-mediated functional progesterone withdrawal is involved in endometrial breakdown in this implant model. These data prompt further studies to determine the homology of this functional progesterone withdrawal mechanism in human endometrium. Mol. Reprod. Dev. 83: 780-791, 2016 © 2016 Wiley Periodicals, Inc.
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Zhou X, Kurowski S, Wu W, Desai K, Chu L, Gutstein DE, Seiffert D, Wang X. A rabbit model of cerebral microembolic signals for translational research: preclinical validation for aspirin and clopidogrel. J Thromb Haemost 2016; 14:1855-66. [PMID: 27262051 DOI: 10.1111/jth.13377] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Indexed: 11/28/2022]
Abstract
UNLABELLED Essentials Microembolic signal (MES) is an independent predictor of stroke risk in patients. A rabbit model of cerebral microembolic signals was established. Therapeutic efficacy was demonstrated for aspirin and clopidogrel on microembolic signals. Potential translational value of this preclinical model of MES was demonstrated. SUMMARY Objectives Cerebral microembolic signals (MESs) detected by transcranial Doppler (TCD) ultrasound constitute an independent predictor of stroke risk and prognosis. The aim of this study was to develop a novel preclinical model of MESs to facilitate translational research. Methods A clinical TCD ultrasound machine was used to detect MESs in the cerebral circulation of New Zealand White rabbits. Technical feasibility was assessed for the measurement of MESs in the middle cerebral artery (MCA) by TCD. FeCl3 -induced carotid arterial thrombosis was optimized for the generation of endogenous microemboli. Ascending doses of two antithrombotic agents (aspirin and clopidogrel) were evaluated individually and in combination for their effects on both arterial thrombosis and MESs in a 30% FeCl3 -induced carotid arterial thrombosis model, along with ex vivo functional assays. Results Dose-dependent FeCl3 -induced arterial thrombosis studies showed that 30% FeCl3 resulted in the most consistent and reproducible MESs in the MCA (3.3 ± 0.7 MESs h(-1) ). Ascending-dose studies showed that the effective doses for 50% inhibition (ED50 ) of thrombus formation, based on integrated blood flow and thrombus weight, respectively, were 3.1 mg kg(-1) and 4.2 mg kg(-1) orally for aspirin, and 0.3 mg kg(-1) and 0.28 mg kg(-1) orally for clopidogrel. The ED50 values for MES incidence were 12.7 mg kg(-1) orally for aspirin, and 0.25 mg kg(-1) orally for clopidogrel. Dual treatment with aspirin (5 mg kg(-1) ) and clopidogel (0.3 mg kg(-1) ) resulted in significant reductions in cerebral MESs (P < 0.05) as compared with monotherapy with either agent. Conclusions Our study demonstrated the successful establishment of the MES model in rabbits, and it may provide translational value for MESs and ischemic stroke research.
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Song Q, Chu X, Zhang X, Bao Y, Zhang Y, Guo H, Liu Y, Liu H, Zhang J, Zhang Y, Chu L. Mechanisms underlying the cardioprotective effect of Salvianic acid A against isoproterenol-induced myocardial ischemia injury in rats: Possible involvement of L-type calcium channels and myocardial contractility. JOURNAL OF ETHNOPHARMACOLOGY 2016; 189:157-164. [PMID: 27211016 DOI: 10.1016/j.jep.2016.05.038] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 03/28/2016] [Accepted: 05/16/2016] [Indexed: 06/05/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Salvianic acid A (SAA), which is the main water-soluble fraction in Radix Salviae Milthiorrhizae, has been widely applied for treating cardiovascular diseases in China. AIM OF THE STUDY To explore the effects of SAA against myocardial ischemia injury induced by isoproterenol (ISO) in rats and to clarify its underlying myocardial protective mechanisms based on l-type calcium channels and myocardial contractility. MATERIALS AND METHODS The myocardial ischemia injured rat model was induced by administering ISO (85mg/kg) subcutaneously at evenly spaced intervals throughout the day and night for 2 consecutive days. Serum cardiac biomarkers were analyzed, and heart tissues were isolated and prepared for histopathology assay. The regulatory effects of SAA on the L-type calcium current (ICa-L) in rat ventricular myocytes were observed by the patch clamp technique. The IonOptix Myocam detection system was used to observe the contractility of isolated rat ventricular myocytes. RESULTS SAA significantly ameliorated changes in heart morphology and electrocardiographic patterns and reduced serum levels of creatine kinase and lactate dehydrogenase in the ISO-induced myocardial ischemia injured rat model. Meanwhile, SAA reduced ICa-L in a concentration-time dependent way with an IC50 of 1.47×10(-5)M, upshifted the current-voltage, activation, and inactivation curves of ICa-L, and significantly inhibited the amplitude of the cell shortening. CONCLUSIONS These results indicate that SAA exhibits significant cardioprotective effects against the ISO-induced myocardial ischemia injury, potentially through inhibiting ICa-L and decreasing myocardial contractility.
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Zhou X, Wu W, Chu L, Gutstein DE, Seiffert D, Wang X. Apixaban Inhibits Cerebral Microembolic Signals Derived from Carotid Arterial Thrombosis in Rabbits. ACTA ACUST UNITED AC 2016; 358:405-12. [DOI: 10.1124/jpet.116.234575] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/29/2016] [Indexed: 11/22/2022]
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Ma Z, Chu L, Liu H, Li J, Zhang Y, Liu W, Dai J, Yi J, Gao Y. Paeoniflorin alleviates non-alcoholic steatohepatitis in rats: Involvement with the ROCK/NF-κB pathway. Int Immunopharmacol 2016; 38:377-84. [PMID: 27351828 DOI: 10.1016/j.intimp.2016.06.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 06/05/2016] [Accepted: 06/21/2016] [Indexed: 02/07/2023]
Abstract
Paeoniflorin (PF) is one of the major active ingredients of Paeonia lactiflora and has been suggested as a dietary therapy for non-alcoholic steatohepatitis (NASH); however, the involved mechanism remains obscure. The present work investigates the anti-inflammatory effects of PF and explores the possible mechanisms in a rat model of NASH. Male Sprague-Dawley rats were fed a high-cholesterol and high-fat (HCF) diet for 12weeks to induce the NASH model, and PF (20mg/kg/d) was orally administered to the NASH rats during the last four weeks of the study. Our results showed that PF significantly decreased serum alanine transferase (ALT) and aspartate transferase (AST) activities and also significantly decreased total levels of cholesterol (TC), low-density lipoprotein (LDL), and tumor necrosis factor alpha (TNF-α) (all P<0.05). Moreover, PF ameliorated the hepatic steatosis and inflammation and inhibited CD68 and transforming growth factor beta (TGF-β)-1 expression (both P<0.05). PF also down-regulated the activity of Rho kinase (ROCK) and suppressed the activation of the nuclear factor (NF)-κB signaling pathway in liver tissue. PF has liver protective and anti-inflammatory effects in HCF diet-induced NASH rats. The possible mechanisms may be associated with inhibition of the ROCK/NF-κB signaling pathway in the NASH liver.
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Chu L, Zhang J, Li YN, Meng X, Liu YY. [Clinical treatment of infective endocarditis with vegetations in pregnant women and the outcomes of gestation]. ZHONGHUA FU CHAN KE ZA ZHI 2016; 51:331-8. [PMID: 27256439 DOI: 10.3760/cma.j.issn.0529-567x.2016.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the clinical treatment of infective endocarditis with vegetations in pregnant women and the outcomes of the gestation. METHODS Nine cases of pregnant women diagnosed as infective endocarditis with vegetations in Beijing Anzhen Hospital, Capital Medical University from January 2001 to October 2015 were enrolled in retrospective analysis. Consultations were held by doctors from department of obstetrics, anesthesiology, cardiology, cardial surgery and extracorporeal circulation to decide the individualized treatment plan for the 9 cases of pregnant women after admissions. Clinical treatments including general treatment, anti-infection treatment, cardiac surgery, and termination of pregnancy surgery were completed through collaboration among related departments. The clinical characters, therapeutic regimens, maternal and neonatal outcomes of the 9 cases were analyzed. RESULTS (1) Clinical characters: the ages of the 9 cases of pregnant women were from 25 to 36 years old. The onset gestational ages were from 19 to 36 weeks. CLINICAL SYMPTOMS fever, cough, sputum and progressive anemia were the main symptoms. Patients had cyanosis of lips, could not lie on the back or even be orthopnea, when heart failure happened. Heart murmur was audible and splenomegaly was touched in physical examination. Blood cultures were positive. Basic heart disease types: 7 cases of congenital heart diseases included 2 cases of aortic insufficiency, 1 case of mitral insufficiency, 1 case of patent ductus arteriosus, 1 case of right ventricular outflow tract stenosis and 2 cases of ventricular septal defect.Two cases of rheumatic heart diseases included 1 case of mitral stenosis, 1 case of mitral stenosis after artificial disc changed and jammed. According to endocardial vegetations attached position there were 3 cases of mitral valve vegetations, 2 cases of pulmonary valve vegetations, 3 cases of aortic vegetations and 1 case of right ventricular outflow tract neoplasm. Preoperative heart function classification: 1 case of level Ⅱ, 3 cases of level Ⅲ, 5 cases of level Ⅳ. (2) TREATMENTS: general treatment included oxygen uptake, rest in bed, cardiac strengthen and diuretic therapy, etc. Combined and adequate antibiotics were applied in anti-infection treatment according to drug sensitive test. Nine cases of pregnant women were all performed surgical treatment of heart diseases and removal of the endocardial vegetations. Caesarean sections were performed for 2 cases in second trimester and for 7 cases in last trimester. Cardiac surgery and caesarean section were operated in 6 cases at the same time among 22-34 weeks of pregnancy. Cardiac surgery were respectively operated in 2 cases 11 days and 32 days after the caesarean section at 33, 37 weeks of pregnancy. While Cardiac surgery was operated (at 26 weeks of pregnancy) before the caesarean section (at 37 weeks of pregnancy) in another 1 case. (3) Maternal and neonatal outcomes: 7 cases of pregnant women were rescued successfully, while 2 cases of pregnant women were death. Postoperative heart function classification: 1 case of level Ⅰ, 2 cases of level Ⅱ, 4 cases of level Ⅲ and 2 cases of level Ⅵ. Neonatal survivals were 6 cases including 2case of full-term infants, 4 cases of preterm infants. Stillbirth or neonatal death were 3 cases, which included 2 cases performed caesarean section in second trimester and 1 case of very low weight infant who was given up treatment by family because of severe asphyxia. Followed up periods were from 1 to 7 years with an average time of (2.0±1.6) years. Infants and young children grew and developed well during the period of follow up. CONCLUSIONS The risk is extremely high of pregnancy with infective endocarditis with vegetations. But there is still a way to save the maternal and neonatal life by using a multidisciplinary collaboration formulation and implementation of individualized treatment plan and selecting the appropriate time for heart surgery and the termination of pregnancy.
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Zhang Y, Zhao X, Chang Y, Zhang Y, Chu X, Zhang X, Liu Z, Guo H, Wang N, Gao Y, Zhang J, Chu L. Calcium channel blockers ameliorate iron overload-associated hepatic fibrosis by altering iron transport and stellate cell apoptosis. Toxicol Appl Pharmacol 2016; 301:50-60. [PMID: 27095094 DOI: 10.1016/j.taap.2016.04.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 03/24/2016] [Accepted: 04/07/2016] [Indexed: 02/07/2023]
Abstract
Liver fibrosis is the principal cause of morbidity and mortality in patients with iron overload. Calcium channel blockers (CCBs) can antagonize divalent cation entry into renal and myocardial cells and inhibit fibrogenic gene expression. We investigated the potential of CCBs to resolve iron overload-associated hepatic fibrosis. Kunming mice were assigned to nine groups (n=8 per group): control, iron overload, deferoxamine, high and low dose verapamil, high and low dose nimodipine, and high and low dose diltiazem. Iron deposition and hepatic fibrosis were measured in mouse livers. Expression levels of molecules associated with transmembrane iron transport were determined by molecular biology approaches. In vitro HSC-T6 cells were randomized into nine groups (the same groups as the mice). Changes in proliferation, apoptosis, and metalloproteinase expression in cells were detected to assess the anti-fibrotic effects of CCBs during iron overload conditions. We found that CCBs reduced hepatic iron content, intracellular iron deposition, the number of hepatic fibrotic areas, collagen expression levels, and hydroxyproline content. CCBs rescued abnormal expression of α1C protein in L-type voltage-dependent calcium channel (LVDCC) and down-regulated divalent metal transporter-1 (DMT-1) expression in mouse livers. In iron-overloaded HSC-T6 cells, CCBs reduced iron deposition, inhibited proliferation, induced apoptosis, and elevated expression of matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of metalloproteinase-1 (TIMP-1). CCBs are potential therapeutic agents that can be used to address hepatic fibrosis during iron overload. They resolve hepatic fibrosis probably correlated with regulating transmembrane iron transport and inhibiting HSC growth.
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Cui R, Chu L, Liu ZQ, Xiao YY, Zhu XL, Chen YJ, Xu Q. Hematologic toxicity assessment in solid tumor patients treated with cetuximab: A pooled analysis of 18 randomized controlled trials. Int J Cancer 2016; 138:2771-3. [PMID: 26789526 DOI: 10.1002/ijc.30004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 01/13/2016] [Indexed: 11/06/2022]
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Schmidt H, Yudhistira I, Chu L, Castro Neto AH, Özyilmaz B, Adam S, Eda G. Quantum Transport and Observation of Dyakonov-Perel Spin-Orbit Scattering in Monolayer MoS_{2}. PHYSICAL REVIEW LETTERS 2016; 116:046803. [PMID: 26871351 DOI: 10.1103/physrevlett.116.046803] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Indexed: 06/05/2023]
Abstract
Monolayers of group 6 transition metal dichalcogenides are promising candidates for future spin-, valley-, and charge-based applications. Quantum transport in these materials reflects a complex interplay between real spin and pseudospin (valley) relaxation processes, which leads to either positive or negative quantum correction to the classical conductivity. Here we report experimental observation of a crossover from weak localization to weak antilocalization in highly n-doped monolayer MoS_{2}. We show that the crossover can be explained by a single parameter associated with electron spin lifetime of the system. At low temperatures and high carrier densities, the spin lifetime is inversely proportional to momentum relaxation time; this indicates that spin relaxation occurs via a Dyakonov-Perel mechanism.
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Zhu F, Chu X, Wang H, Zhang X, Zhang Y, Liu Z, Guo H, Liu H, Liu Y, Chu L, Zhang J. New Findings on the Effects of Tannic Acid: Inhibition of L-Type Calcium Channels, Calcium Transient and Contractility in Rat Ventricular Myocytes. Phytother Res 2016; 30:510-6. [PMID: 26762248 DOI: 10.1002/ptr.5558] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 12/03/2015] [Accepted: 12/05/2015] [Indexed: 11/07/2022]
Abstract
Tannic acid (TA) is a group of water-soluble polyphenolic compounds that occur mainly in plant-derived feeds, food grains and fruits. Many studies have explored its biomedical properties, such as anticancer, antibacterial, antimutagenic, antioxidant, antidiabetic, antiinflammatory and antihypertensive activities. However, the effects of TA on the L-type Ca(2+) current (ICa-L) of cardiomyocytes remain undefined. The present study examined the effects of TA on ICa-L using the whole-cell patch-clamp technique and on intracellular Ca(2+) handling and cell contractility in rat ventricular myocytes with the aid of a video-based edge detection system. Exposure to TA resulted in a concentration- and voltage-dependent blockade of ICa-L, with the half maximal inhibitory concentration of 1.69 μM and the maximal inhibitory effect of 46.15%. Moreover, TA significantly inhibited the amplitude of myocyte shortening and peak value of Ca(2+) transient and increased the time to 10% of the peak. These findings provide new experimental evidence for the cellular mechanism of action of TA and may help to expand clinical treatments for cardiovascular disease.
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Wu S, Yin X, Fang X, Zheng J, Li L, Liu X, Chu L. c-MYC responds to glucose deprivation in a cell-type-dependent manner. Cell Death Discov 2015; 1:15057. [PMID: 27551483 PMCID: PMC4979460 DOI: 10.1038/cddiscovery.2015.57] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/14/2015] [Accepted: 10/21/2015] [Indexed: 12/17/2022] Open
Abstract
Metabolic reprogramming supports cancer cells’ demands for rapid proliferation and growth. Previous work shows that oncogenes, such as MYC, hypoxia-inducible factor 1 (HIF1), have a central role in driving metabolic reprogramming. A lot of metabolic enzymes, which are deregulated in most cancer cells, are the targets of these oncogenes. However, whether metabolic change affects these oncogenes is still unclear. Here we show that glucose deprivation (GD) affects c-MYC protein levels in a cell-type-dependent manner regardless of P53 mutation status. GD dephosphorylates and then decreases c-MYC protein stability through PI3K signaling pathway in HeLa cells, but not in MDA-MB-231 cells. Role of c-MYC in sensitivity of GD also varies with cell types. c-MYC-mediated glutamine metabolism partially improves the sensitivity of GD in MDA-MB-231 cells. Our results reveal that the heterogeneity of cancer cells in response to metabolic stress should be considered in metabolic therapy for cancer.
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Liu T, Chu X, Wang H, Zhang X, Zhang Y, Guo H, Liu Z, Dong Y, Liu H, Liu Y, Chu L, Zhang J. Crocin, a carotenoid component of Crocus cativus, exerts inhibitory effects on L-type Ca(2+) current, Ca(2+) transient, and contractility in rat ventricular myocytes. Can J Physiol Pharmacol 2015; 94:302-8. [PMID: 26674933 DOI: 10.1139/cjpp-2015-0214] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Crocin, a carotenoid component of Crocus sativus L. belonging to the Iridaceae family, has demonstrated cardioprotective effects. To investigate the cellular mechanisms of these cardioprotective effects, here we studied the influence of crocin on L-type Ca(2+)current (I(Ca-L)), intracellular Ca(2+) ([Ca(2+)]i), and contraction of isolated rat cardiomyocytes by using the whole-cell patch-clamp technique and video-based edge detection and dual excitation fluorescence photomultiplier systems. Crocin inhibited I(Ca-L) in a concentration-dependent manner with the half-maximal inhibitory concentration (IC50) of 45 μmol/L and the maximal inhibitory effect of 72.195% ± 1.54%. Neither current-voltage relationship of I(Ca-L), reversal potential of I(Ca-L), nor the activation/inactivation of I(Ca-L) was significantly changed. Crocin at 1 μmol/L reduced cell shortening by 44.64% ± 2.12% and the peak value of the Ca(2+) transient by 23.66% ± 4.52%. Crocin significantly reduced amplitudes of myocyte shortening and [Ca(2+)]i with an increase in the time to reach 10% of the peak (Tp) and a decrease in the time to 10% of the baseline (Tr). Thus, the cardioprotective effects of crocin may be attributed to the attenuation of [Ca(2+)]i through the inhibition of I(Ca-L) in rat cardiomyocytes and negative inotropic effects on myocardial contractility.
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Ma XG, Liu YF, Liu N, Ren JC, Xu GW, Chu L, Lv H, Huang CY, Zhu YF. Magnetic mediation effect of a C impurity in a Mn-doped Zn₁₂O₁₂ nanocluster: a case of multiple exchange interactions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:335301. [PMID: 26235128 DOI: 10.1088/0953-8984/27/33/335301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The stability and exchange interaction mechanism of a doped Zn12O12 cluster with Mn and C atoms were investigated by first-principles calculations. For the Mn-doped Zn12O12 cluster, it is identified that a superexchange interaction deriving the hybridization between the Mn 3d(2/x)-2/y and O 2p(xy) orbitals dominates the Mn(↑)-Mn(↓) antiferromagnetic coupling, although a direct exchange interaction deriving the Mn-Mn bonding is also found. In order to turn the Mn spin state in the Mn-doped Zn12O12 cluster, C doping is undertaken to change the magnetic interactions of these impurities. It is proved that the C incorporation into the Mn-doped Zn12O12 cluster destroys the short-ranged antiferromagnetic coupling, where multiple exchange interactions take over, including the direct exchange interaction and the kinetic p-d exchange interaction partially due to the geometric distortion and surface effect with dangling bonds (sp(2)-like hybrids). It is concluded that the kinetic p-d exchange interaction plays a dominant role in Mn/C-doped Zn12O12 clusters.
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Li M, Zhang L, Lu B, Chen Z, Chu L, Meng L, Fan Y. Role of dendritic cell-mediated abnormal immune response in visceral hypersensitivity. Int J Clin Exp Med 2015; 8:13243-13250. [PMID: 26550249 PMCID: PMC4612934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 07/22/2015] [Indexed: 06/05/2023]
Abstract
The role of dendritic cells (DCs) in irritable bowel syndrome (IBS) is unclear. This study tested the hypothesis that intestinal DCs induced visceral hypersensitivity in IBS rats through mast cell (MC) activation. The IBS rat model was established by combining colorectal distension with restraint stress. The number of CD103-positive cells in colon was higher in the IBS group. Expression of PAR-2, IL-4 and IL-9 in the colonic mucosa was higher in the IBS group. Mesenteric lymph node DCs (MLNDCs) and splenic CD4(+)/CD8(+) T cells were isolated and purified by a magnetic labeling-based technique; they were cultured alone or co-cultured (T4+DC/T8+DC). The coculture of MLNDCs and CD4(+) T cells had the highest IL-4 secretion in the IBS group, while IL-9 expression was higher in the cultures containing CD8(+) T cells. Our findings indicate that an increased number of DCs in the colon stimulated CD4(+) T cells to secrete high levels of IL-4, which led to the activation of MCs and subsequently resulted in visceral hypersensitivity.
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Chu L, Rennie D, Cockcroft D, Pahwa P, Dosman J, Hagel L, Karunanayake C, Lawson J. Agreement between questionnaire report of allergy-related outcomes in school-age children and objective measures of atopy: the Saskatchewan rural health study. Clin Exp Allergy 2015; 45:1337-45. [DOI: 10.1111/cea.12533] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 03/10/2015] [Accepted: 03/16/2015] [Indexed: 12/25/2022]
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Hu X, Wang H, Lv X, Chu L, Liu Z, Wei X, Chen Q, Zhu L, Cui W. Cardioprotective Effects of Tannic Acid on Isoproterenol-Induced Myocardial Injury in Rats: Further Insight into 'French Paradox'. Phytother Res 2015; 29:1295-1303. [PMID: 25989747 DOI: 10.1002/ptr.5376] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 04/01/2015] [Accepted: 04/28/2015] [Indexed: 11/11/2022]
Abstract
Tannic acid (TA) is a polyphenolic compound, which has shown diverse pharmacological effects with antimutagenic, anticarcinogenic and antibactericidal properties. However, cardioprotective effects of TA have not been reported. To investigate the protective effects of TA, rats were administered TA for 7 days and then intoxicated with isoproterenol (ISO). Myocardial ischemia injury was indicated by changes in electrocardiographic (ECG) patterns, morphology and cardiac marker enzymes. Furthermore, protein expression levels of c-fos, c-jun, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), cleaved-caspase-3 and -9 were analyzed by immunohistochemistry, and activities of apoptosis-related proteins Bax, Bcl-2, caspase-3 and nuclear factor kappa B (NF-κB) were detected by Western blot. Pretreatment with TA ameliorated changes in morphology and ECG, reduced activities of marker enzymes, suppressed overexpression of apoptosis-related proteins, upregulated expression of antioxidants. Moreover, TA pretreatment contributed to the decrease in ratio of Bax/Bcl-2, as well as reduced expression of TNF-α, IL-1β, caspase-3, cleaved-caspase-3 and -9. TA displayed cardioprotective effects, which may be attributed to lowering of Bax/Bcl-2 ratio, c-fos and c-jun expression and inhibition of NF-κB activation, as well as oxidative stress, inflammation and apoptosis. These findings provide further insight into the 'French paradox' and the mechanisms underlying the beneficial effects of TA. Copyright © 2015 John Wiley & Sons, Ltd.
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Yang Y, Xu H, Shen J, Yang Y, Wu S, Xiao J, Xu Y, Liu XY, Chu L. RGD-modifided oncolytic adenovirus exhibited potent cytotoxic effect on CAR-negative bladder cancer-initiating cells. Cell Death Dis 2015; 6:e1760. [PMID: 25973680 PMCID: PMC4669706 DOI: 10.1038/cddis.2015.128] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 04/02/2015] [Accepted: 04/06/2015] [Indexed: 11/21/2022]
Abstract
Cancer-initiating cell (CIC) is critical in cancer development, maintenance and recurrence. The reverse expression pattern of coxsackie and adenovirus receptor (CAR) and αν integrin in bladder cancer decreases the infection efficiency of adenovirus. We constructed Arg-Gly-Asp (RGD)-modified oncolytic adenovirus, carrying EGFP or TNF-related apoptosis-inducing ligand (TRAIL) gene (OncoAd.RGD-hTERT-EGFP/TRAIL), and applied them to CAR-negative bladder cancer T24 cells and cancer-initiating T24 sphere cells. OncoAd.RGD-hTERT-EGFP had enhanced infection ability and cytotoxic effect on T24 cells and T24 sphere cells, but little cytoxicity on normal urothelial SV-HUC-1 cells compared with the unmodified virus OncoAd.hTERT-EGFP. Notably, OncoAd.RGD-hTERT-TRAIL induced apoptosis in T24 cells and T24 sphere cells. Furthermore, it completely inhibited xenograft initiation established by the oncolytic adenovirus-pretreated T24 sphere cells, and significantly suppressed tumor growth by intratumoral injection. These results provided a promising therapeutic strategy for CAR-negative bladder cancer through targeting CICs.
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Zhang Y, Wang H, Cui L, Zhang Y, Liu Y, Chu X, Liu Z, Zhang J, Chu L. Continuing treatment with Salvia miltiorrhiza injection attenuates myocardial fibrosis in chronic iron-overloaded mice. PLoS One 2015; 10:e0124061. [PMID: 25850001 PMCID: PMC4388639 DOI: 10.1371/journal.pone.0124061] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 02/28/2015] [Indexed: 12/27/2022] Open
Abstract
Iron overload cardiomyopathy results from iron accumulation in the myocardium that is closely linked to iron-mediated myocardial fibrosis. Salvia miltiorrhiza (SM, also known as Danshen), a traditional Chinese medicinal herb, has been widely used for hundreds of years to treat cardiovascular diseases. Here, we investigated the effect and potential mechanism of SM on myocardial fibrosis induced by chronic iron overload (CIO) in mice. Kunming male mice (8 weeks old) were randomized to six groups of 10 animals each: control (CONT), CIO, low-dose SM (L-SM), high-dose SM (H-SM), verapamil (VRP) and deferoxamine (DFO) groups. Normal saline was injected in the CONT group. Mice in the other five groups were treated with iron dextran at 50 mg/kg per day intraperitoneally for 7 weeks, and those in the latter four groups also received corresponding daily treatments, including 3 g/kg or 6 g/kg of SM, 100 mg/kg of VRP, or 100 mg/kg of DFO. The iron deposition was estimated histologically using Prussian blue staining. Myocardial fibrosis was determined by Masson's trichrome staining and hydroxyproline (Hyp) quantitative assay. Superoxide dismutase (SOD) activity, malondialdehyde (MDA) content and protein expression levels of type I collagen (COL I), type I collagen (COL III), transforming growth factor-β1 (TGF-β1) and matrix metalloproteinase-9 (MMP-9) were analyzed to investigate the mechanisms underlying the effects of SM against iron-overloaded fibrosis. Treatment of chronic iron-overloaded mice with SM dose-dependently reduced iron deposition levels, fibrotic area percentage, Hyp content, expression levels of COL I and COL III, as well as upregulated the expression of TGF- β1 and MMP-9 proteins in the heart. Moreover, SM treatment decreased MDA content and increased SOD activity. In conclusion, SM exerted activities against cardiac fibrosis induced by CIO, which may be attributed to its inhibition of iron deposition, as well as collagen metabolism and oxidative stress.
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Chen W, Yao J, Chu L, Yuan Z, Li Y, Zhang Y. Genetic mapping of the nulliplex-branch gene (gb_nb1) in cotton using next-generation sequencing. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2015; 128:539-47. [PMID: 25575840 DOI: 10.1007/s00122-014-2452-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 12/24/2014] [Indexed: 05/21/2023]
Abstract
Using bulked segregant analysis based on next-generation sequencing, the recessive nulliplex-branch gene was mapped between two SNP markers ~600 kb apart. In a "nulliplex-branch" cotton mutant, most of the flowers arise directly from leaf axils on the main shoot, which usually does not have a fruiting branch. A nulliplex-branch is a useful trait by which to study cotton architecture; however, the genetic basis of this mutant has remained elusive. In this study, bulked segregant analysis combined with next-generation sequencing technology was used to finely map the underlying genes that result in a nulliplex-branch plant. The nulliplex-branch Pima cotton variety, Xinhai-18, was crossed with the normal branch upland cotton line, TM-1, resulting in an F2 population. The nulliplex-branch trait was found to be controlled by the recessive gene gb_nb1. Allelic single-nucleotide polymorphisms (SNPs) were discovered by reduced-representation sequencing between the parents, and their profiles were also characterized in the nulliplex-branch and normal branch bulks constructed using the F2 plants. A candidate ~9.0 Mb-long region comprising 42 SNP markers was found to be associated with gb_nb1, which helped localize it at the ~600-kb interval on Chr 16 by segregation analysis in the F2 population. The closely linked markers with gb_nb1 developed in this study will facilitate the marker-assisted selection of the nulliplex-branch trait, and the fine map constructed will accelerate map-based cloning of gb_nb1.
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Chu L, Zhao H, Fang J, Li C, Liu Z, Cui R, Hu F, Zhang X, Chen Y, Han H, Cao C, Xu Q. The traditional Chinese medicinal formula BDL301 suppresses tumor growth by inhibiting STAT3 pathway and inducing apoptosis in colorectal cancer cells. DNA Cell Biol 2015; 34:178-88. [PMID: 25607688 DOI: 10.1089/dna.2014.2532] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The traditional Chinese medicinal formula BDL301 has been used to inhibit inflammation for hundreds of years. The development of colorectal cancer and chronic inflammation are closely related. In this study, we investigated whether BDL301 could inhibit tumor growth. We found that angiogenesis and tumor growth were both inhibited in vivo. In addition, apoptosis was induced and the signal transducer and activator of transcription-3 (STAT3) pathway were suppressed in the colorectal cancer cells in vitro and in vivo by BDL301. This study demonstrates that BDL301 exerted significant anticancer activity by inhibiting the STAT3 pathways and inducing apoptosis in colorectal cancer cells.
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Guan S, Ma J, Chu X, Gao Y, Zhang Y, Zhang X, Zhang F, Liu Z, Zhang J, Chu L. Effects of total flavones from Acanthopanax senticosus on L-type calcium channels, calcium transient and contractility in rat ventricular myocytes. Phytother Res 2015; 29:533-9. [PMID: 25586009 DOI: 10.1002/ptr.5278] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 11/28/2014] [Accepted: 12/01/2014] [Indexed: 11/11/2022]
Abstract
Acanthopanax senticosus (Rupr. et Maxim.) Harms (AS), a traditional herbal medicine, has been widely used to treat ischemic heart disease. However, the underlying cellular mechanisms of its benefits to cardiac function remain unclear. The present study examined the effects of total flavones from AS (TFAS) on L-type Ca(2+) channel currents (ICa-L ) using the whole cell patch-clamp technique and on intracellular calcium ([Ca(2+) ]i ) handling and cell contractility in rat ventricular myocytes with the aid of a video-based edge-detection system. Exposure to TFAS resulted in a concentration- and voltage-dependent blockade of ICa-L , with the half-maximal inhibitory concentration (IC50 ) of 283.12 µg/mL and the maximal inhibitory effect of 36.49 ± 1.95%. Moreover, TFAS not only increased the maximum current in the current-voltage relationship but also shifted the activation and inactivation curves of ICa-L toward the hyperpolarizing direction. Meanwhile, TFAS significantly reduced amplitudes of myocyte shortening and [Ca(2+) ]i with an increase in the time to 10% of the peak (Tp) and a decrease in the time to 10% of the baseline (Tr). Thus, the cardioprotective effects of TFAS may be attributed mainly to the attenuation of [Ca(2+) ]i through the direct inhibition of ICa-L in rat ventricular myocytes and consequent negative effect on myocardial contractility.
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