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OBJECTIVE@#To assess the efficacy and safety of Taohong Siwu Decoction (, TSD), a Chinese herbal compound prescription, in patients with angina pectoris (AP).@*METHODS@#Randomized clinical trials (RCTs) comparing TSD plus conventional treatment (CT) with CT plus placebo or CT only in the patients with AP were searched in PubMed, Cochrane Library, Excerpta Medica Database, Chinese National Knowledge Infrastructure, Chinese Biomedical Literature Database, Wanfang Database, Chinese Scientific Journal Database, Chinese Clinical Trial Registry and International Clinical Trial Registry from their inception to March 2017. The primary outcomes include a composite event of death, acute myocardial infarction (AMI), and target vessel revascularization. The secondary outcomes include angina symptom, electrocardiogram (ECG) improvement and serum high-sensitivity C-reactive protein (hs-CRP), endothelin-1 (ET-1), triglycerides (TG), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels. The methodological quality of included studies and extracted available data were assessed. RevMan 5.3 software was used to conduct statistical analysis. The relative risk (RR) and standardized mean difference (SMD) with 95% confidence interval (CI) was calculated. A funnel plot was used to evaluate the publication bias.@*RESULTS@#Among 204 studies identified in the literature search, 12 trials including 959 patients with AP met the inclusion criteria. No studies reported the primary outcome including death, AMI and target vessel revascularization. TSD combined with CT showed significant improvement in relieving angina symptom [RR=3.70, 95% CI (2.42, 5.67)] and ECG [RR=3.20, 95% CI (2.20, 4.65)] compared with CT alone. TSD combined with CT reduced the serum hs-CRP, TG, TC and LDL-C levels compared with CT alone. No serious adverse events were reported in TSD combined with CT.@*CONCLUSIONS@#TSD combined with CT has a potential benefit on relieving AP without significant adverse events. However, the efficacy on the cardiovascular events needs to be assessed by more rigorously-designed, largescale, and multi-center RCTs in future.
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The intestinal absorption characteristics of ten iridoid glycosides and phenolic acids in the Pterocephali Herba were evaluated via rat intestinal valgus model. The intestinal sac fluids at different time after administration of high,medium and low concentrations of Pterocephali Herba extract were collected and ten chemical components in fluid samples were detected by UPLC-PDA. Accumulative absorbed doses( Q) and absorption rate constants( Ka) of ten chemical constituents were calculated,while proportions between Pterocephali Herba extract and intestinal absorption liquid were compared. The results showed that the intestinal absorption of 10 chemical components was linear absorption( R2>0. 9) at different concentrations,which accorded with the zero-order absorption rate. The absorption rate constant was related to the concentration of the drug and the intestinal site,which indicated that intestinal adsorption mechanism of the components were passive diffusion and active transport. Proportions of chemical constituents in intestinal sac fluid were different from those in Pterocephali Herba extract. Therefore,those ten chemical components in Pterocephali Herba extract can be absorbed in whole intestine. Everted intestinal sac model can be used to evaluate intestinal absorption characteristics of ingredients in Pterocephali Herba extract effectively.
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Animais , Ratos , Caprifoliaceae , Química , Medicamentos de Ervas Chinesas , Farmacocinética , Absorção Intestinal , Intestinos , Extratos Vegetais , Farmacocinética , Ratos Sprague-DawleyRESUMO
In order to study the interaction between Pterocephalus hookeri and bitter taste receptors,three-dimensional structural models of bitter taste receptors TAS2 R16,TAS2 R14 and TAS2 R13 were established by homology modeling in this paper. Maestro software was used for docking the chemical constituents of P. hookeri with bitter taste receptors. The results showed that 25 chemical components of P. hookeri can regulate three bitter taste receptors. And these components were mainly iridoid glycosides and phenolic acids.This research focused on the comprehensive application of homology modeling and molecular docking technology to explore the interaction between bitter chemical constituents of P. hookeri and bitter taste receptors. This study provided assistance in revealing pharmacodynamic basis of bitter Tibetan medicine at molecular level. It also provided new ideas and methods for the study of Tibetan medicine.
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Humanos , Caprifoliaceae , Química , Correlação de Dados , Medicina Tradicional Tibetana , Simulação de Acoplamento Molecular , Receptores Acoplados a Proteínas G , Metabolismo , PaladarRESUMO
"Qi medicinal herbs" in China refers to a kind of regional national folk herbs related to the treatment of five labors and seven injuries,the last word of which is "Qi". Our study is to sort out and standardize the name and basic confused varieties through the establishment of " Qi medicinal herbs" VFP information database. " Qi medicinal herbs" variety sorting model of " literature research-variety survey-data mining-spatial distribution" was developed by means of literature analysis which the names and varieties of " Qi medicinal herbs" in the literature were summarized and sorted out. The relationship between the distribution of " Qi medicinal herbs" resources and the use of ethnic groups were visualized by Cytoscape 2. 8. 0 software. The information database of " Qi medicinal herbs" involved in 230 kinds of medicinal materials which including 211 species of plants( including varieties) from 66 families. Medicinal materials standard in China have 9 kinds of " Qi medicinal herbs". Among them,there are 31 kinds of " Qi medicinal herbs" with the confusion of " the different names of the same" and " the different substance of the same names". The most used ethnic groups are Tujia,Qiang and Miao. The main efficacy is clearing heat and detoxification,dispelling wind and removing dampness,etc.,and the main treatment is for injury,rheumatic arthralgia and so on. Names and varieties of " Qi medicinal herbs" among Chinese ethnic groups and folk are standardized and sorted out,which is served to promotethe " Qi medicinal herbs" reasonable protection and utilization of resources,and provide effective reference for exploring the information technology and geographical distribution of ethnic medicine and standardizing clinical medication.
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Humanos , China , Medicamentos de Ervas Chinesas , Padrões de Referência , Medicina Tradicional Chinesa , Plantas Medicinais , Classificação , Qi , Terminologia como AssuntoRESUMO
<p><b>BACKGROUND</b>Calreticulin (CRT) is major Ca 2+ -binding chaperone mainly resident in the endoplasmic reticulum (ER) lumen. Recently, it has been shown that non-ER CRT regulates a wide array of cellular responses. We previously found that CRT was up-regulated during hypoxia/reoxygenation (H/R) and this study was aimed to investigate whether CRT nuclear translocation aggravates ER stress (ERS)-associated apoptosis during H/R injury in neonatal rat cardiomyocytes.</p><p><b>METHODS</b>Apoptosis rate and lactate dehydrogenase (LDH) leakage in culture medium were measured as indices of cell injury. Immunofluorescence staining showed the morphological changes of ER and intracellular translocation of CRT. Western blotting or reverse transcription polymerase chain reaction was used to detect the expression of target molecules.</p><p><b>RESULTS</b>Compared with control, H/R increased apoptosis rate and LDH activity. The ER became condensed and bubbled, and CRT translocated to the nucleus. Western blotting showed up-regulation of CRT, Nrf2, activating transcription factor 4 (ATF4), CHOP and caspase-12 expression after H/R. Exogenous CRT overexpression induced by plasmid transfection before H/R increased cell apoptosis, LDH leakage, ER disorder, CRT nuclear translocation and the expression of ERS-associated molecules. However, administration of the ERS inhibitor, taurine, or CRT siRNA alleviated cell injury, ER disorder, and inhibited ERS-associated apoptosis.</p><p><b>CONCLUSIONS</b>Our results indicated that during H/R stress, CRT translocation increases cell apoptosis and LDH leakage, aggravates ER disorder, up-regulates expression of nuclear transcription factors, Nrf2 and ATF4, and activates ERS-associated apoptosis.</p>
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Animais , Ratos , Apoptose , Genética , Fisiologia , Calreticulina , Genética , Metabolismo , Hipóxia Celular , Genética , Fisiologia , Sobrevivência Celular , Genética , Fisiologia , Células Cultivadas , Estresse do Retículo Endoplasmático , Fisiologia , Miócitos Cardíacos , Biologia Celular , Metabolismo , Interferência de RNARESUMO
BACKGROUND:Rapid and complete reperfusion has been widely adopted in the treatment of patients with acute myocardial infarction (AMI), but this process sometimes can cause severe reperfusion injury. This study aimed to investigate different patterns of post-conditioning in acute myocardial ischemia-reperfusion injury, and to detect the role of mitogen activated protein kinase (MAPK) during the injury. METHODS:Rats were randomly divided into five groups:sham group, reperfusion injury (R/I) group, gradually decreased reperfusion group (GDR group, 30/10-25/15-15/25-10/30 seconds of reperfusion/ischemia), equal reperfusion group (ER group, 20/20 seconds reperfusion/ischemia, 4 cycles), and gradually increased reperfusion group (GIR group, 10/30-15/25-25/15-30/10 seconds of reperfusion/ischemia). Acute myocardial infarction and ischemic post-conditioning models were established in the rats. Six hours after reperfusion, 3 rats from each group were sacrificed and myocardial tissues were taken to measure the expressions of phosphorylation of extracellular signal-regulated protein kinase (P-ERK), phosphorylated c-Jun N-terminal kinase (P-JNK), mitogen-activated protein kinase p38 (p38 MAPK), tumor necrosis factor-α (TNF-α), caspases-8 in the myocardial tissue, and cytochrome c in the cytosol using Western blot. Hemodynamics was measured at 24 hours after reperfusion, the blood was drawn for the determination of cardiac enzymes, and the heart tissue was collected for the measurement of apoptosis using TUNEL. One-way analysis of variance and the Q test were employed to determine differences in individual variables between the 5 groups. RESULTS:Three post-conditioning patterns were found to provide cardioprotection (P<0.05) compared with R/I without postconditioning. GIR provided the best cardioprotection effect, followed by ER and then GDR. Apoptotic index and serum marker levels were reduced more significantly in GIR than in ER (P<0.05). The enhanced cardioprotection provided by GIR was accompanied with significantly increased levels of P-ERK 1/2 (1.82±0.22 vs. 1.54±0.32,P<0.05), and lower levels of p-JNK, p38 MAPK, TNF-α, caspase-8, caspase-9 and cytochrome in the cytoplasm (P<0.05), compared with ER. The infarct size was smaller in the GIR group than in the ER group, but this difference was not significant (16.30%±5.22% vs. 20.57%±6.32%,P<0.05). Allthe measured variables were improved more significantly in the GIR group than in the GDR group (P<0.05). CONCLUSION:Gradually increased reperfusion in post-conditioning could attenuate reperfusion injury more significantly than routine method, thereby the MAPK pathway plays an important role in this process.
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<p><b>BACKGROUND</b>Ischemic postconditioning (I-postC) is a newly discovered and more amenable cardioprotective strategy capable of protecting the myocardium from ischemia/reperfusion (I/R) injury. Endoplasmic reticulum (ER) is a principal site for secretary protein synthesis and calcium storage. Myocardial I/R causes ER stress and emerging studies suggest that the cardioprotection has been linked to the modulation of ER stress. The aim of the present study was to determine whether cardioprotection of I-postC involves reduction in ER stress through calcineurin pathway.</p><p><b>METHODS</b>In the in vivo model of rat myocardial I/R, myocardial infarct size was measured by triphenyltetrazolium chloride (TTC) staining and apoptosis was detected using terminal eoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. Expression of calreticulin, C/EBP homologous protein (CHOP), caspase-12, and activation of caspase-12 in myocardium were detected by Western blotting. The activity and expression of calcineurin in myocardium were also detected.</p><p><b>RESULTS</b>I-postC protected the I/R heart against apoptosis, myocardial infarction, and leakage of lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB). I-postC suppressed I/R-induced ER stress, as shown by a decrease in the expression of calreticulin and CHOP, and caspase-12 activation. I-postC downregulated calcineurin activation in myocardium subjected to I/R.</p><p><b>CONCLUSION</b>I-postC protects myocardium from I/R injury by suppressing ER stress and calcineurin pathways are not associated with the I-postC-induced suppression of ER stress-related apoptosis.</p>
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Animais , Masculino , Ratos , Apoptose , Fisiologia , Western Blotting , Calcineurina , Metabolismo , Creatina Quinase Forma MB , Sangue , Estresse do Retículo Endoplasmático , Fisiologia , Hemodinâmica , Pós-Condicionamento Isquêmico , L-Lactato Desidrogenase , Sangue , Infarto do Miocárdio , Sangue , Metabolismo , Traumatismo por Reperfusão Miocárdica , Sangue , Metabolismo , Miocárdio , Metabolismo , Patologia , Miócitos Cardíacos , Biologia Celular , Proteínas Proto-Oncogênicas c-bcl-2 , Metabolismo , Ratos Sprague-Dawley , Proteína X Associada a bcl-2 , MetabolismoRESUMO
<p><b>OBJECTIVE</b>The effects of various postconditioning algorithm on reperfusion injury and the role of mitochondrion pathway were investigated in a rat model of reperfusion/injury.</p><p><b>METHODS</b>Rats were divided into 5 groups: sham, reperfusion/injury (R/I group), reverse algorithm of postconditioning (R-Post, 30/10-25/15-15/25-10/30 s of reperfusion/re-occlusion), standard algorithm of postconditioning (S-Post, 4 cycles of 20/20 s of reperfusion/re-occlusion), and gradual algorithm of postconditioning (G-Post, 10/30-15/25-25/15-30/10 s of reperfusion/re-occlusion).</p><p><b>RESULTS</b>The levels of Bax, Cytochrome-c, Caspase-9, serum marker of myocardium and apoptosis index were significantly lower while the level of Bcl-2 was significantly higher in the three postconditioning groups than those in R/I group (all P < 0.05). The levels of Bax (0.35 +/- 0.10 vs. 0.50 +/- 0.02, P < 0.05), Cytochrome-c (0.66 +/- 0.16 vs. 1.68 +/- 0.22, P < 0.05), Caspase-9 (0.61 +/- 0.17 vs. 1.66 +/- 0.55, P < 0.05), serum marker of myocardium [CK: (251.00 +/- 45.16) U/L vs. (388.56 +/- 75.01) U/L, P < 0.05; CK-MB: (146.00 +/- 60.12) U/L vs. (291.16 +/- 52.41) U/L, P < 0.05] and apoptosis index [(4.32 +/- 1.16)% vs. (8.58 +/- 1.12)% , P < 0.05] were all significantly lower while Bcl-2 level (2.00 +/- 0.34 vs. 1.40 +/- 0.18, P < 0.05) was significantly higher in G-Post group than those in S-Post group. Moreover, above mentioned cardiac protective effects were significantly stronger in the G-Post group compared to R-Post group (all P < 0.05).</p><p><b>CONCLUSION</b>In conclusion, gradual algorithm of postconditioning could attenuate reperfusion injury more significantly than standard algorithm, and mitochondrion pathway plays an important role in this cardioprotective process.</p>
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Animais , Ratos , Algoritmos , Caspase 9 , Metabolismo , Citocromos c , Metabolismo , Pós-Condicionamento Isquêmico , Mitocôndrias , Metabolismo , Traumatismo por Reperfusão Miocárdica , Metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Metabolismo , Ratos Sprague-Dawley , Proteína X Associada a bcl-2 , MetabolismoRESUMO
<p><b>OBJECTIVE</b>To test whether postconditioning could inhibit the expression of phospho-JNK (P-JNK) mitogen activated protein kinase (MAPK) and study its relation to apoptosis of cardiocyte.</p><p><b>METHODS</b>Sixty rats were randomly divided into six groups: sham, reperfusion injury (R/I), postconditioning (Post), SP600125 (I_JNK), anisomycin and postconditioning (Ani+Post) and anisomycin (Ani) groups. After acute myocardial infarction was induced in rats, placebo solution (DMSO), SP600125 (6 mg/kg) or anisomycin (2 mg/kg) was injected through jugular vein 5 min before reperfusion; 6 h later 3 rats of each group were executed and the hearts were separated to measure the signaling molecules (phospho-JNK, TNF alpha, Caspase-8, Bcl-2/Bax, cytochrome-c). Twenty-two hours later hemodynamic data were measured in the left rats, and then blood samples were taken to determine serum markers of cardiac damage, and hearts were separated to measure the infarction area and cardiocyte apoptosis.</p><p><b>RESULT</b>Postconditioning improved +/-DP/DTmax of left ventricle, limited infarct area, relieved apoptosis and necrosis of cardiocytes, and inhibited the expression of P-JNK (1.12 +/-0.21 Compared with 1.90 +/-0.32, P<0.05). At the same time the levels of TNFalpha Caspase-8, Bax and Cyt-c were lower in Post group than those in R/I group, but Bcl-2 expression levels were higher. I_JNK group presented the similar protection effect of postconditioning [TUNEL index: (6.23 +/-2.43)% Compared with (18.22 +/-5.10)%, P<0.05; Infarct area: (23.44 +/-6.34)% Compared with (42.31 +/-8.21)%, P<0.05]. On the other hand, Ani+Post group partially lost cardioprotection effect [TUNEL index: (14.12 +/-2.00)% Compared with (18.22 +/-5.10)%,P>0.05; Infarct area: (35.27 +/-5.28)% Compared with (42.31+/-8.21)%,P>0.05], because of the activation of JNK MAPK.</p><p><b>CONCLUSION</b>Postconditioning can inhibit phosphorylation of JNK MAPK, which attenuates cardiocyte apoptosis by both extrinsic and mitochondria pathway.</p>
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Animais , Masculino , Ratos , Apoptose , Precondicionamento Isquêmico Miocárdico , Proteínas Quinases JNK Ativadas por Mitógeno , Metabolismo , Farmacologia , Infarto do Miocárdio , Patologia , Terapêutica , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Patologia , Distribuição Aleatória , Ratos Sprague-DawleyRESUMO
Endoplasmic reticulum stress (ERS) is an adaptive process in response to circumstantial changes, but excessive and/or prolonged ERS can induce cell apoptosis. C/EBP homologous protein (CHOP) is a very important marker participating in ERS-associated cell apoptosis, while the role of the myocyte apoptosis induced by CHOP remains unclear in the development of hypertrophy. The present study aimed to investigate the effect of CHOP-mediated ERS-associated apoptosis on myocardial hypertrophy induced by abdominal aortic constriction in rats. Healthy male Wistar rats were randomly divided into model group (n=45) and control group (n=40). The rats in model group received abdominal aortic constriction. Hemodynamic changes, whole heart weight/body weight (HW/BW) and left ventricular weight/body weight (LVW/BW) were measured on 1 d, 3 d, 7 d, 14 d and 28 d after surgery, respectively. The mRNA expression of glucose-regulated protein 78 (GRP78), calreticulin (CRT) and CHOP, which are important markers of ERS, were detected by RT-PCR, and Western blot was used to assess the protein level of GRP78, CRT, CHOP, and apoptosis-associated proteins, Bax and Bcl-2. The results obtained were as follows. Compared with control group, the blood pressure, LVW/BW, and HW/BW of rats in model group increased significantly and cardiac function enhanced compensatively on 7 d after surgery, and increased progressively during the experiment. As early as 1 d after surgery, the mRNA level of CRT in model group increased by 136% (P< 0.01) compared with control, while the protein expression increased by 69.2% on 7 d after surgery (P<0.01). Both mRNA and protein expression of GRP78 increased by 20% and 186% (P<0.01) respectively on 7 d after surgery, and the expression sustained high level during the experiment afterwards. Correlation analysis indicated a positive correlation between +dp/dt(max) and CRT protein expression (r=0.780, P<0.01) as well as GRP78 protein expression (r=0.694, P<0.01). Prolonged ERS triggered myocyte apoptosis, as both the mRNA and protein level of CHOP in model group increased by 22.2% (P<0.01) and 76.0% (P<0.01) respectively compared with control on 7 d after hypertrophy (14 d after surgery), and meanwhile, the protein expression of pro-apoptotic Bax increased by 41.1% (P<0.01) and anti-apoptotic Bcl-2 protein expression decreased by 25.5% (P<0.01). Correlation analysis indicated a positive correlation between CHOP and Bax expression (r=0.654, P<0.01), and a negative correlation between CHOP and Bcl-2 expression (r=-0.671, P<0.01). These results suggest that abdominal aortic constriction induces a significant up-regulation in ER molecular chaperones at early stage of post-surgery, indicating that ERS response is activated in the rat heart; while prolonged ERS could lead to myocyte apoptosis, and CHOP-mediated ERS-associated apoptosis may contribute to myocardial hypertrophy. We speculate that cell apoptosis may take part in the regulation of myocardial hypertrophy and heart failure, and determine the progression of decompensated hypertrophy.
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Animais , Masculino , Ratos , Aorta , Apoptose , Calreticulina , Metabolismo , Constrição , Estresse do Retículo Endoplasmático , Proteínas de Choque Térmico , Metabolismo , Hipertrofia , Patologia , Miocárdio , Patologia , Ratos Wistar , Fator de Transcrição CHOP , Metabolismo , Regulação para Cima , Proteína X Associada a bcl-2 , MetabolismoRESUMO
Calreticulin (CRT) is an essential Ca(2+)-binding chaperone existing in endoplasmic reticulum (ER) or sarcoplasmic reticulum (SR), and is involved in intracellular Ca(2+) homeostasis and protein folding. Ischemic postconditioning (I-postC), a newly discovered endogenous protective phenomenon, induces CRT up-regulation. The present study aimed to investigate the cardioprotective mechanism of CRT up-regulation induced by hypoxic postconditioning (H-postC). Primary cultured neonatal rat cardiomyocytes were exposed to 2 h of hypoxia followed by 24 h of reoxygenation. Postconditioning was carried out by two cycles of 10 min of reoxygenation and 20 min of rehypoxia after 2 h of hypoxia. Antisense oligodeoxynucleotides (AS-ODNs) were used to inhibit CRT expression 36 h before hypoxia. Cardiomyocytes were randomly divided into 6 groups as follows (n=4): control, hypoxia/reoxygenation (H/R), H-postC, AS, AS + H/R, and AS + H-postC. Morphological studies, lactate dehydrogenase (LDH) activity assay in culture medium, and flow cytometry were used to detect cardiomyocyte necrosis and apoptosis. Intracellular Ca(2+) concentration was detected by fluorescent Fluo-3/AM staining through laser confocal microscope, and p-nitrophenyl phosphate (PNPP) was used as substrate to measure calcineurin (CaN) activity. The expression of CRT, CaN, nuclear factor kappa B (NFκB) and apoptosis-related proteins, such as Bcl-2, Bax and C/EBP homologous protein (CHOP) were detected by Western blot. The results were as follows. (1) H-postC protected neonatal cardiomyocytes from H/R injury. Compared with H/R group, cell survival rate increased by 17.1%, apoptotic rate and LDH leakage decreased by 6.67% and 27.9% in H-postC group, respectively (P<0.05). (2) H-postC induced mild up-regulation of CRT expression. Inhibition of CRT by AS-ODNs attenuated the cardioprotection of H-postC partly. Compared with H-postC group, cell survival rate decreased by 8.98%, and apoptotic rate and LDH leakage increased by 1.74% and 13.6% in AS + H-postC group, respectively (P<0.05), but intracellular Ca(2+) concentration, CaN activity, and expression of CaN and NFκB did not change significantly (P>0.05), suggesting that CRT participates in endogenous protection, not through Ca(2+)-CaN pathway. (3) H-postC inhibited the expression of pro-apoptosis proteins such as Bax and CHOP, but induced up-regulation of anti-apoptosis protein Bcl-2. Inhibition of CRT by AS-ODNs partly inhibited the changes in apoptosis-related proteins expression induced by H-postC, suggesting that CRT participates in the anti-apoptosis effect of H-postC through regulating expression of apoptosis-related proteins. These results indicate that CRT up-regulation induced by H-postC is involved in the cardioprotection through regulating expression of apoptosis-related proteins, not through Ca(2+)-CaN pathway in neonatal cardiomyocytes.
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Animais , Ratos , Apoptose , Calcineurina , Metabolismo , Calreticulina , Metabolismo , Hipóxia Celular , Sobrevivência Celular , Células Cultivadas , Pós-Condicionamento Isquêmico , Miócitos Cardíacos , Metabolismo , Oxigênio , Metabolismo , Regulação para CimaRESUMO
Sarcoplasmic reticulum is a principal subcellular organelle which regulates calcium homeostasis, protein synthesis, and apoptosis of cardiomyocytes. Endoplasmic reticulum (ER) stress is defined as the perturbation of ER function which is caused by the alterations in the ER environment, such as the perturbation of Ca(2+) homeostasis, elevated protein synthesis, the deprivation of glucose, altered glycosylation, and the accumulation of misfolded proteins. Moderate ER stress is able to restore cellular homeostasis, i.e., to exert a compensatory effect on cardiomyocytes. However, intense or persistent ER stress may cause ER stress-induced apoptosis, which shifts the hypertrophied myocardium to failure, and affects the pathogenesis and development of myocardial hypertrophy. The article reviewed the role of ER stress response in the pathogenesis and development of myocardial hypertrophy.
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Animais , Apoptose , Estresse do Retículo Endoplasmático , Homeostase , Hipertrofia , Patologia , Miocárdio , Patologia , Miócitos Cardíacos , Patologia , Biossíntese de Proteínas , Retículo Sarcoplasmático , PatologiaRESUMO
The present study was aimed to investigate whether calreticulin (CRT) was involved in the protective effect of hypoxic preconditioning (HPC) against oxidative stress injury in rat cardiomyocytes. Neonatal cardiomyocytes were prepared from Sprague-Dawley rats aged 24 h, and cultured in DMEM medium containing 10% fetal bovine serum. The cultured cardiomyocytes were randomly divided into 8 groups as follows: (1) hydrogen peroxide stress (H(2)O(2) group); (2) brief hypoxic exposure for 20 min to simulate HPC (HPC group); (3) hypoxic exposure for 20 min followed by normoxic reoxygenation for 24 h before hydrogen peroxide stress (HPC + H(2)O(2) group); (4) SB203580 (a specific inhibitor of p38 MAPK) + HPC + H(2)O(2) group; (5) CRT antisense oligonucleotide transfection (AS group); (6) AS + H(2)O(2) group; (7) AS + HPC + H(2)O(2) group; (8) control group. Morphological observation, lactate dehydrogenase (LDH) leakage and flow cytometry were employed to assess cell apoptosis and necrosis. RT-PCR and Western blot were used to detect CRT expression and activity of p38 MAPK. All experiments were repeated at least four separate times. The results obtained were as follows: (1) HPC relieved cell injury caused by H(2)O(2). Compared with that in H(2)O(2) group, the cell survival rate increased by 18.0% (P<0.05), apoptotic rate and LDH leakage in culture medium decreased by 19.4% and 53.0%, respectively (P<0.05) in HPC + H(2)O(2) group. (2) H(2)O(2) induced CRT over-expression (7.1-fold increase compared with control, P<0.05), while HPC resulted in mild CRT up-regulation (2.4-fold increase compared with control, P<0.05), suggesting that HPC can relieve the over-expression of CRT induced by H(2)O(2). (3) CRT AS transfection weakened the protection of HPC. Compared with that in HPC + H(2)O(2) group, the cell survival rate decreased by 4% (P<0.05), and apoptotic rate and LDH leakage in culture medium increased by 2.6% and 39.0%, respectively (P< 0.05) in AS + HPC + H(2)O(2) group. (4) The protection of HPC and HPC-induced upregulation of CRT were almost eliminated when SB203580 was administered before HPC. These results suggest that HPC up-regulates CRT expression through the p38 MAPK signaling pathway and protects cardiomyocytes from oxidative stress injury.
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Animais , Ratos , Apoptose , Calreticulina , Metabolismo , Hipóxia Celular , Sobrevivência Celular , Células Cultivadas , Peróxido de Hidrogênio , Imidazóis , Farmacologia , Precondicionamento Isquêmico Miocárdico , L-Lactato Desidrogenase , Metabolismo , Miócitos Cardíacos , Patologia , Estresse Oxidativo , Piridinas , Farmacologia , Ratos Sprague-Dawley , Transdução de Sinais , Regulação para Cima , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
<p><b>OBJECTIVE</b>To analyze the residues of heavy metals in Chinese crude drugs.</p><p><b>METHOD</b>The SPSS 13.0 software was used to analyze the data of Cu, Pb, As, Cd, Hg collected in literatures. And, Green Trade Standards of Importing & Exporting Medicinal Plants & Preparations was used as the standard to evaluate the pollution condition of Cu, Pb, As, Cd, Hg in Chinese crude drugs.</p><p><b>RESULT</b>Chinese crude drugs were contaminated by heavy metals in different levels. The content of Cu, Pb, As, Cd, Hg exceeded the limit of the standard and the percentage was 21.0%, 12.0%, 9.7%, 28.5%, 6.9%, respectively; the phenomena of two, three and four metals exceeding limited standard simultaneity in a drug were also found and the percentage was 4.6%, 1.5%, 0.7%, respectively; the content of heavy metals in Radix Platycodi, Radix Asari and Rhizoma Coptidis was higher among the thirty-six Chinese crude drugs; All of the content of five heavy metals in Barbary Fructus Lycii Rhizoma Anemones Raddeanae, Radix Panacis Quiquefolii and Fructus Aurantii were below the limit; The pollution levels of heavy metals in different locality were different; The content of Cu, Pb in cultivated Chinese crude drugs was higher than that in wild Chinese crude drugs, while the content of As in wild Chinese crude drugs was higher than that in cultivated Chinese crude drugs.</p><p><b>CONCLUSION</b>The pollution levels of heavy metals in Chinese crude drugs were detailed reported in this paper. And it provided ways for the further study of heavy metals in Chinese crude drugs.</p>
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Cádmio , Cobre , Medicamentos de Ervas Chinesas , Química , Chumbo , Mercúrio , Metais PesadosRESUMO
<p><b>OBJECTIVE</b>Overexpression of SERCA2a could improve cardiac function in human and experimental heart failure (HF) models. We observed the proteomics changes post SERCA2a overexpression in a pacing induced HF model in dogs.</p><p><b>METHODS</b>Beagles were divided into four groups: control group, HF group (230 beats/min for 4 weeks), HF + EGFP group (myocardial injection of 1 x 10(12) v.g recombinant adeno-associated virus carrying enhanced green fluorescent protein gene, rAAV2/1-EGFP) and HF + SERCA2a group (myocardial injection of 1 x 10(12) v.g recombinant adeno-associated virus carrying SERCA2a gene, rAAV2/1-SERCA2a). Thirty days after gene transduction, left ventricular systolic and diastolic functions were measured by echocardiography and invasive hemodynamics in all animals. By use of 2-dimensional gel electrophoresis (2-DE), -500 distinct protein spots were detected in myocardium of all animals. Protein spots observed to be altered between failing and SERCA2a overexpressed hearts were subjected to tryptic peptide mass fingerprinting for identification by MALDI-TOF mass spectrometry in combination with LC/MS/MS analysis.</p><p><b>RESULTS</b>At 30 day after gene transfer, HF signs were significantly reduced, cardiac function [LVSP: (214.72 +/- 31.74) mm Hg (1 mm Hg = 0.133 kPa) vs. (139.32 +/- 36.79) mm Hg, +dp/dt(max): (6779.43 +/- 217.58) mm Hg/s vs. (2746.85 +/- 931.23) mm Hg/s and -dp/dt(max): (-4341.42 +/- 322.02) mm Hg/s vs. (-2531.14 +/- 616.15) mm Hg/s, LVEDP: (21.86 +/- 6.95) mm Hg vs. (59.78 +/- 6.92) mm Hg] significantly improved in HF + SERCA2a dogs than those in HF + EGFP group(all P < 0.05) and parameters were comparable between HF + SERCA2a and control groups. We identified alterations in the expression level of more than 10 proteins in myocardium. These protein changes were observed mainly in two subcellular compartments: the cardiac contractile apparatus and metabolism/energetics.</p><p><b>CONCLUSION</b>These results showed that overexpression of SERCA2a could improve cardiac function accompanied with numerous alterations in protein expressions involved in calcium handling, myofibrils, and energy production in this dog model of chronic heart failure.</p>
Assuntos
Animais , Cães , Modelos Animais de Doenças , Terapia Genética , Insuficiência Cardíaca , Genética , Metabolismo , Terapêutica , Contração Miocárdica , Proteoma , Retículo Sarcoplasmático , Química , Metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Genética , Metabolismo , Transdução Genética , Remodelação VentricularRESUMO
<p><b>OBJECTIVE</b>To characterize properties of Rhizoma Dioscoreae polysaccharide-Fe (III) complex (RDPC) and analyze its composition.</p><p><b>METHOD</b>Physicochemical properties, such as character, solubility and stability of RDPC were studied. Surface structure of RDPC was studied by Infrared spectroscopic technique and transmission electron microscopy. The content of Fe (III) in RDPC was determined by o-phenanthroline spectrophotometry after being treated by ashing, wet digestion, or direct dissolution methods. Content of polysaccharide in RDPC was determined by sulphuric acid-phenol method.</p><p><b>RESULT</b>RDPC was brownish red powder. It could dissolve in water, its aqueous solution was very stable at the pH from 3.8 to 11.6. RDPC was a surface complex in which polysaccharide combined with beta-FeOOH as core. The content of Fe (III) in RDPC was 17.05%, 16.53%, 17.10% respectively after being treated by 3 different pretreatment methods. Content of polysaccharide in RDPC was 16.27%.</p><p><b>CONCLUSION</b>This is the first report of RDPC which was stable under physiological pH conditions and could be a new candidate for iron-supplementary.</p>
Assuntos
Dioscoreaceae , Química , Medicamentos de Ervas Chinesas , Química , Ferro , Química , Microscopia Eletrônica de Transmissão , Polissacarídeos , QuímicaRESUMO
<p><b>OBJECTIVE</b>To study the chemical constituents of Dioscorea opposita.</p><p><b>METHOD</b>The chemical constituents were isolated and purified by silica gel column chromatography, and the structures were elucidated by their spectroscopic data and physico-chemical properties.</p><p><b>RESULT</b>Twelve compounds were obtained and identified as palmitic acid (1), beta-sitosterol (2), oleic acid (3), beta-sitosterol acetate (4), 5-(hydroxymethyl)furfural (5), nonanedioic acid (6), beta-daucosterol (7), cyclo-(Phe-Tyr) (8), cyclo-(Tyr-Tyr) (9), 6-methyl citrate (10), 1, 5-dimethyl citrate (11), trimethyl citrate (12).</p><p><b>CONCLUSION</b>Compounds 3-12 were isolated from this plant for the first time and cyclodipeptides were firstly isolated from the Dioscoreae family; Compound 9 was a new natural product.</p>
Assuntos
Cromatografia em Gel , Dioscorea , Química , Medicamentos de Ervas Chinesas , Química , Espectroscopia de Ressonância Magnética , Espectrometria de MassasRESUMO
The present study was aimed to investigate the effect of ischemic postconditioning (I-postC) on ischemia/reperfusion (I/R) injury and whether calreticulin (CRT) is involved in its intracellular signal transduction both in vivo and in cultured skeletal muscle cells. I/R injury in the right hind limb of healthy male Wistar rats was induced by clamping the right femoral artery, and the rats were randomly divided into 3 groups (n=16): I/R group (4-hour ischemia/12- or 24-hour reperfusion), ischemic preconditioning (IPC) group (3 cycles of 1-minute ischemia/1-minute reperfusion) and I-postC group (3 cycles of 5-minute reperfusion/5-minute ischemia). The left hind limb was used as control. Lactate dehydrogenase (LDH) activity in blood plasma, wet/dry weight ratio (W/D) and ultramicrostructure of skeletal muscle were detected 12 h or 24 h after reperfusion. Cultured skeletal muscle cells from neonatal Sprague-Dawley (SD) rat were divided into 6 groups: hypoxia/reoxygenation (H/R) group, hypoxic postconditioning (H-postC) group, hypoxic preconditioning (HPC) group, cyclosporine A (CsA) + H-postC group, CsA + H/R group and control group. H/R was produced by 2-hour hypoxia/24-hour reoxygenation. The survival rate and apoptotic rate of skeletal muscle cells in each group were measured. Western blot was used to detect the expressions of CRT and calcineurin (CaN). The results were as follows: (1) During in vivo experiment, compared with I/R, I-postC significantly decreased LDH activity and W/D, attenuated the ultramicrostructure injury of skeletal muscle and the apoptosis of nucleolus. 12 h and 24 h after reperfusion, compared with that in I/R group, the expression of CRT in I-postC group increased by 439% and 102%, respectively (P<0.05), and the expression of CaN increased by 196% and 63%, respectively (P<0.05). Correlation analysis indicated a positive correlation between CRT and CaN expressions (r=0.865, P<0.01). (2) In cultured skeletal muscle cells, H-postC attenuated cell injury induced by H/R. Compared with those in H/R group, CRT and CaN expressions in H-postC increased by 31.8% (P<0.05) and 6.02%, respectively. The protection of H-postC and CaN up-regulation were eliminated when CsA, the inhibitor of CaN, was added before H-postC. Both in vivo and in vitro results indicate that I-postC, similar as IPC, can protect the skeletal muscle against I/R injury, and its effects may be mediated by CRT and CaN up-regulation. The inhibition of CaN expression may also attenuate the protective effects of I-postC.
Assuntos
Animais , Masculino , Ratos , Apoptose , Calcineurina , Calreticulina , Fisiologia , Células Cultivadas , Hipóxia , Pós-Condicionamento Isquêmico , Precondicionamento Isquêmico , Músculo Esquelético , Ratos Sprague-Dawley , Ratos Wistar , Traumatismo por Reperfusão , Transdução de Sinais , Regulação para CimaRESUMO
Restoration of blood flow is the definitive therapy to salvage myocardium following ischemic injury. Sudden restoration of blood flow to the ischemic myocardium may, however, also cause reperfusion injury. Therefore, to prevent such ischemia/reperfusion (I/R) injury, one strategy could be to evoke endogenous myocardial protective mechanisms. Ischemic preconditioning (IPC) and postconditioning (I-postC) are endogenous protective mechanisms capable of protecting the myocardium from myocardial infarction, stunning, and ventricular arrhythmia induced by I/R injury. The mechanisms involve induction of triggers, activation of signaling pathways, and end-effectors, which attenuate generation of free radicals and calcium overload induced by I/R. The fact that I-postC can be applied after a prolonged period of ischemia offers a novel approach to myocardial protection. This article mainly reviews the cardioprotection, mechanisms, and application to clinical cardiology of I-postC.
Assuntos
Animais , Humanos , Arritmias Cardíacas , Síndrome de Brugada , Doença do Sistema de Condução Cardíaco , Sistema de Condução Cardíaco , Anormalidades Congênitas , Pós-Condicionamento Isquêmico , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Miocárdio , Traumatismo por Reperfusão , Transdução de SinaisRESUMO
Exposure of endothelial cells (ECs) to hypoxia leads to a decrease in EC proliferation. However, the mechanism by which hypoxia inhibits EC proliferation is unclear. Perlecan has been reported to play an important role in regulating EC proliferation. We hypothesized that perlecan was involved in the hypoxia-induced inhibition of EC proliferation. To test this hypothesis, rat cardiac microvascular ECs were cultured under normoxic or hypoxic conditions for 12 h and harvested for determination of perlecan mRNA expression using real-time reverse transcription-polymerase chain reaction (RT-PCR). The results showed that exposure of ECs to hypoxia for 12 h induced a decrease in perlecan mRNA expression (61.72%, P<0.05). Concomitantly, the down-regulation of endogenous perlecan induced by hypoxia or the neutralization of endogenous perlecan with anti-perlecan antibody significantly inhibited EC proliferation and responsiveness to basic fibroblast growth factor (bFGF), and decreased focal adhesion kinase (FAK) expression and extracellular signal-regulated kinase 1/2 (ERK1/2) activation. These data indicate that down-regulation of perlecan expression contributes to hypoxia-induced inhibition of rat cardiac microvascular EC proliferation by suppressing FAK-mediated and ERK1/2-dependent growth signals.