ABSTRACT
OBJECTIVE To explore the mechanism of Tingli dazao xiefei decoction on ventricular remodeling in model rats with heart failure after myocardial infarction. METHODS The rat model of heart failure after myocardial infarction was established by ligation of anterior descending branch of left coronary artery， which was divided into 8 groups： sham operation group， model group， A779 group （1 mg/kg）， A779 （1 mg/kg）+Tingli dazao xiefei decoction equivalent-dose group （0.8 g/kg）， A779 （1 mg/kg） +Tingli dazao xiefei decoction high-dose group （1.6 g/kg）， Tingli dazao xiefei decoction equivalent-dose group （0.8 g/kg）， Tingli dazao xiefei decoction high-dose group （1.6 g/kg） and losartan potassium group （10 mg/kg）. Each group was given equal volume of distilled water or corresponding drugs intragastrically for 4 weeks. Masson staining was used to determine the distribution of collagen fibers in rat myocardium. The content of hydroxyproline （Hyp） in myocardium was determined by alkaline hydrolyzation. The expressions of type Ⅰ and Ⅲ collagen （COLⅠ， COLⅢ）in myocardium were detected by immunohisto-chemistry. Myocardial fibrosis-related indexes such as matrix metalloproteinase-2 （MMP-2）， MMP-9， tissue inhibitor of metalloproteinase-1 （TIMP-1） and soluble suppression of tumorigenicity-2 （sST-2） were detected by ELISA. The protein expressions of angiotensin converting enzyme 2-angiotensin-（1-7）-Mas [ACE2-Ang-（1-7）-Mas] axis were detected by Western blot. RESULTS Compared with sham operation group， myocardial cells in model group and A779 group were disordered， collagen fiber deposition was significantly increased and myocardial fibrosis was obvious； the Hyp content and MMP-2， MMP-9， sST-2 levels were increased， and COL Ⅰ and COL Ⅲ positive expressions were significantly enhanced； TIMP-1 level， protein expressions of ACE2， Ang-（1-7） and Mas were significantly decreased （P＜0.05）. Compared with model group， above indexes of Tingli dazao xiefei decoction equivalent-dose and high-dose groups were improved to different extents. Compared with A779 group， A779+Tingli dazao xiefei decoction equivalent-dose and A779+high-dose groups could improve myocardial arrangement and collagen distribution， reduce the Hyp content and MMP-2， MMP-9 levels， reduce positive expressions of COL Ⅰ and COL Ⅲ （P＜0.05）， but couldn’t improve Ang-（1-7） and Mas protein expression. CONCLUSIONS Tingli dazao xiefei decoction can improve ventricular remodeling in myocardial failure model rats after myocardial infarction by improving the expression of ACE2- Ang（- 1-7）-Mas axis proteins.
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OBJECTIVE：To investigate the effects of Shenfu yixin decoction on the utilization of fatty acid in primary hypoxic cardiomyocytes and its potential mechanism. METHODS ：The apical tissue of neonatal SD rats with 1-3 days old were collected ， and the primary cardiomyocytes were isolated ，cultured and identified. The cardiomyocytes were randomly divided into normal group，model group ，coenzyme Q 10 group（positive control ，1×10－4 mol/L），Shenfu yixin decoction low-dose and high-dose groups（0.25，0.5 mg/mL）. Except for normal group ，cells in other groups were cultured under 5％O2，5％CO2 and 90％N2 for 6 hours to induce hypoxic injury model. After 6 hours of hypoxia ，the content of ATP was detected by luciferase luminescence assay. Western blotting assay was adopted to detect the expression of FAT/CD 36，PPARα and PPARβ/δ. RESULTS：Compared with normal group ，the content of ATP and relative expression of FAT/CD 36 protein were decreased significantly in model group （P＜ 0.05）. Compared with model group ，the content of ATP was increased significantly in coenzyme Q 10 group and Shenfu yixin decoction high-dose group ，while the relative expression of FAT/CD 36 and PPARα protein in coenzyme Q10 group，the relative expression of FAT/CD 36 protein in Shenfu yixin decoction high-dose group as well as the relative expression of PPARα and PPARβ/δ protein in Shenfu yixin decoction groups were decreased significantly （P＜0.05）. CONCLUSIONS ：Shenfu yixin decoction can inhibit the utilization of fatty acid of primary hypoxic cardiomyocytes and improve their energy metabolism by inhibiting the expression of FAT/CD 36，PPARα and PPARβ/δ protein.
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OBJECTIVE： To observe the effects of Shenfu yixin decoction on reactive oxygen species （ROS） and energy metabolism in primary hypoxic cardiomyocytes. METHODS： After isolation， culture and identification， primary cardiomyocytes of neonatal SD rats were randomly divided into normal group， model group， positive control group （coenzyme Q10， 0.1 mmol/L） and Shenfu yixin decoction low-dose and high-dose groups （0.25， 0.5 mg/mL）. Except for normal group， other groups were cultured with 5％O2， 5％CO2 and 90％N2 for 6 h to induce hypoxic injury model. After 6 hours of hypoxia， ROS contents in cardiomyocytes and mitochondria of each group were detected by ROS probe and flow cytometry. Luciferase luminescence and Western blotting were used to detect ATP content and CK protein expression of each group. Transmission electron microscope was used to observe ultrastructure of cardiomyocytes in each group. RESULTS： Compared with normal group， the expression of ROS in primary hypoxic cardiomyocytes and mitochondria as well as the content of ROS were increased significantly， while the content of ATP and expression levels of CK protein were decreased significantly （P＜0.05）； there were swelling of endoplasmic reticulum and mitochondria， dissolution or even disappearance of mitochondrial ridge， obvious cardiomyocytes injury. Compared with model group， the expression of ROS in primary hypoxic cardiomyocytes and mitochondria of administration groups， the contents of ROS in primary hypoxic cardiomyocytes of positive control group and Shenfu yixin decoction high-dose group as well as the content of ROS in primary hypoxic cardiomyocytes mitochondria of administration groups were all decreased significantly， while ATP contents in primary hypoxic cardiomyocytes of positive control group and Shenfu yixin decoction high-dose group as well as expression levels of CK protein in primary hypoxic cardiomyocytes of administration groups were all increased significantly （P＜0.05）. The primary hypoxic cardiomyocytes injury was relieved significantly in positive control group and Shenfu yixin decoction high-dose group. CONCLUSIONS： Shenfu yixin decoction can improve primary hypoxic cardiomyocytes， down-regulate the expression of ROS in cardiomyocytes and mitochondria and also improve its energy metabolism.
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Objective This study was designed to determine the effect of transient receptor potential vanilloid type 4(TRPV4)on angiotensin Ⅱ(Ang Ⅱ)-induced renal injury in TRPV4-null mutant(TRPV4 -/-)mice. Methods The mice were divided into sham group and Ang Ⅱ-treated group. Ang Ⅱ was infused systemically into wild type(WT)and TRPV4 -/- mice via a miniosmotic pump for 4 weeks, and the sham mice were given with normal saline. Systolic blood pressure,urinary excretion of albumin and 8-isoprostane, serum creatinine, and the pathological changes in the kidney tissues were assayed after the 4-week treatment. Results Compared with corresponding sham mice,Ang Ⅱ infusion led to enhanced systolic blood pressure,increased urinary excretion of albumin and 8-isoprostane,increased serum creatinine(P< 0.05),and enhanced glomerulosclerosis degree and renal tubulointerstitial injury index(P< 0.05)in the WT and TRPV4 -/- mice. The result were associated with enhanced collagen levels in the kidney(P< 0.05). All of them were attenuated by the deletion of TRPV4 in the absence of alteration in blood pressure(P< 0.05). Conclusions Deletion of TRPV4 could alleviate renal injury during Ang Ⅱ-induced hypertension, suggesting that TRPV4 may contribute to the pathophysiology of angiotensin Ⅱ-induced renal injury.
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This study was aimed to explore the method to improve the purity of primary myocardial cells from neonatal rats. The myocardial tissues of rats which were born 1-3 days were repeated digested by 0.08% myocardial cells digestive juices. And then, cells were neutralized with DMEM medium which containing 10% fetal bovine serum. The cells were separated with differential sidewall ion. The red blood cell cracking liquid was added to remove the red blood cells. Bromine deoxidization uracil (Brdu) was added to purify the myocardial cells. Then, cells were incubated in the CO2 incubator for two days. The serum-free synchronization was performed for one day. The results showed that the output of myocardial cells from one rat was about 1.2 × 106. The dynamic myocardial cells occupied more than 90%. The purity of myocardial cells was more than 90%. After 3 to 4 days, the cell fusion of myocardial cells was formed with spontaneous rhythm beats. It was concluded that the method can ensure the yield and the activity of the myocardial cells. At the same time, the purity of myocardial cells can also be improved greatly.
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This study was aimed to observe the effect ofJia-Shen prescription (JSP) on angiotensinⅡ (AngⅡ) inhibition, ventricular remodeling in myocardial infarction (MI) rat model. The anterior descending coronary artery of Sprague-Dawley rat was ligated to establish the MI rat model. Rats were randomly divided into the 3 g JSP group, 6 g JSP group, losartan group, model group, and the sham-operation group. Intragastric administration of medication was given 24 h after MI. In the 3 g and 6 g JSP group, JSP was given at the dose of 3 g·kg-1·day-1 and 6 g·kg-1day-1, respectively. Losartan was given at the dose of 10 mg·kg-1·day-1 in the losartan group. Same volume of distilled water was given to the sham-operation and model group. Four weeks later, the left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD), posterior wall thickness (PWT), left ventricular ejection fraction (LVEF), left ventricular fractional shorten (LVFS), left ventricular weight index (LVWI), the distribution and content of collagen, plasma brain natriuretic peptide (BNP) and the AngⅡ content in myocardial tissues homogenate were observed. The results showed that 4 weeks after MI, compared to the model group, 6 g PJP reduced myocardial infarct size, LVWI, LVEDD and LVESD, and enhanced LVEF and LVFS (P< 0.05). In ischemic regions, compared to the model group, JSP can obviously reduce the content of collagen (P < 0.05). This effect had dose-dependent relationship. Plasma BNP and AngⅡ content in myocardial tissues homogenate were also obviously lower than the model group (P< 0.05). It was concluded that JSP can improve the ventricular remodeling of MI rat model. Its action mechanism may be through the AngⅡ inhibition, in order to improve the early stage left ventricular morphological remodeling, myocardial fibrosis and cardiac contractile function.
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This article was aimed to determine effects of Jia-Shen prescription (JSP) on infarct size (IS), cardiac function and myocardial cytokine in the early phase of myocardial infarction (MI) in rats. Acute MI models were induced by the ligation of left anterior descending coronary artery in Sprague-Dawley (SD) rats. The rats were ran-domly divided into five groups, which were the sham-operated group, model group, JSP-3 g (3 g·kg-1·day-1) group, JSP-6 g (6 g·kg-1·day-1) group, and the losartan (10 mg·kg-1·day-1) group. IS was determined by Evans blue and 2,3,5-Triphenyltetrazolium chloride (TTC) 3 days after MI. The left ventricular structure and contractility were measured by echocardiography performed 7 days after MI. And contents of myocardial inflammatory mediators in-cluding tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), and monocyte chemoattractant protein-1 (MCP-1) were measured by ELISA. The results showed that compared with the model group, treatment with JSP at the dose of 6 g significantly reduced myocardial IS (P<0.05);left ventricular end diastolic diameter (LVEDD) and left ventricu-lar end systolic diameter (LVESD) were significantly decreased (P<0.05); left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) were significantly increased (P<0.05).The results were similar as the losartan group. Compared with the model group, JSP can significantly reduce the production of TNF-α, IL-1βand MCP-1 in cardiac tissues (P<0.05). Except TNF-α, these effects of JSP were in a dose-dependent manner. JSP (6 g) had equal effectiveness with losartan. It was concluded that consistent with losartan-induced cardioprotection, JSP administered after MI reduced myocardial IS, improved cardiac function, and decreased inflammatory mediators in ischemic myocardium. The data indicated that JSP exerted its cardioprotection possibly via inhibiting inflammatory response.