Early diagnosis of rats with acute myocardial infarction by measurement of brain natriuretic peptide

Cardioprotective Effects of Tetrahydropalmatine on Acute Myocardial Infarction in Rats

Tetrahydropalmatine (THP) is an active component of Corydalis yanhusuo W. T. Wang. The current study investigates the possible cardioprotective effects of tetrahydropalmatine in acute myocardial ischemia (AMI) rats. The anterior descending coronary artery of SD rats was ligated to establish an AMI model. After two weeks of gavage of THP, cardiac function was determined by echocardiography. The organ index and the infarct size were assessed after the experiment, and the histopathological myocardial tissue changes were observed. In addition, the apoptosis index of myocardial cells was detected by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The levels of SOD, MDA, CAT, GSH-Px, BNP, and cTn-I were measured by enzyme-linked immunosorbent assay. To determine relevant proteins, the Western blot and molecular docking were applied. Compared with the model group, THP could enhance rat cardiac ejection function to improve cardiac function, drastically lessen the infarct size, reduce myocardial cell damage and inflammatory cell infiltration. THP might also prevent ischemic myocardial damage by inhibiting myocardial cell apoptosis and efficiently reducing oxidative stress. Specifically, THP could decrease MDA, BNP, c-TnI activities, as well as the expression of Bax and Caspase-3 protein, while increasing SOD, GSH-Px, CAT activities, and Bcl-2 level. Furthermore, THP could significantly promote the phosphorylation of PI3K and Akt proteins. The involved pathways and proteins have also been verified through molecular docking. According to these findings, THP may preserve the myocardium due to its anti-oxidant and anti-apoptotic properties.

Restoration of cardiac metabolic flexibility by acetate in high fat diet-induced obesity is independent of ANP/BNP modulation

The present study hypothesized that cardiac metabolic inflexibility is dependent on cardiac ANP/BNP alteration and HDAC activity. We further sought to investigate the therapeutic potential of SCFA, acetate in high fat diet (HFD)-induced obese rat model. Adult male Wistar rats were assigned into groups (n = 6/group): Control, Obese, Sodium acetate (NaAc)-treated and Obese+ NaAc-treated groups received distilled water once daily (oral gavage), 40% HFD ad libitum, 200 mg/kg NaAc once daily (oral gavage) and 40% HFD+NaAc respectively. The treatments lasted for 12 weeks. HFD resulted in increased food intake, body weight and cardiac mass. It also caused insulin resistance and enhanced β-cell function, increased fasting insulin, lactate, plasma and cardiac triglyceride, total cholesterol, lipid peroxidation, TNF-α, IL-6, HDAC and cardiac troponin T and γ-Glutamyl transferase and decreased plasma and cardiac GSH with unaltered cardiac ANP and BNP. However, these alterations were averted when treated with acetate. Taken together, these results indicate that obesity induces defective cardiac metabolic flexibility, which is accompanied by elevated level of HDAC and not ANP/BNP alteration. The results also suggest that acetate ameliorates obesity-induced cardiac metabolic inflexibility by suppression of HDAC and independent of ANP/BNP modulation.

Ameliorative role of Ulva extract against heavy metal mixture-induced cardiovascular through oxidative/antioxidant pathways and inflammatory biomarkers

The current study investigates the therapeutic and curative effect of Ulva lactuca polyphenolic extract (ULPE) in general and particularly polyphenolics compounds against heavy metal mixture (HME). The toxicity behind heavy metal is due to oxidative stress resulted from heavy metals pollution or administration through contaminated food (vegetables, water, and fish). Heavy metal toxicity plays a major role in different cardiovascular diseases. The objective of this study is aimed to examine the protective effect of ULPE against heavy metal mixture induced cardiovascular diseases through oxidative/antioxidant and inflammatory pathways. Sixty male rats (Sprague-Dawley) were assigned to six groups. Group I served as the control, group II served as the induced group receiving subcutaneously for 7 days 0.25 mg/100 gm body weight/day heavy metal mixtures (Equal concentration of Ni, Cd, Co and Hg chloride, and Pb acetate), group III received (i.p.) ULPE of dose 30 mg for 15 days, group IV served as the protected group pretreated with ULPE for 15 days as a protection dose, and then treated with the heavy metal-mixture, group V served as protected standard group pretreated with vitamin C (VitC ) (50 mg/Kg) and then treated with the heavy metal-mixture, and group VI served as standard group treated with VitC (50 mg/Kg). The main pathological changes within the heart revealed heart inflammation after heavy-metal mixtures administrations. On contrast to the protected group treated with ULPE (group IV), the protection group (group II) showed a significant increase in the antioxidant as well as anti-inflammatory biomarker. The cardiovascular biomarkers (Troponin T, CRP, and BNP) showed similar attitude elevations in induction group and decreased greatly in protection and VitC group. The antioxidant and the anti-inflammatory activities of ULPE are a consequence of their higher polyphenolic contents as well as marine secondary metabolites which are confirmed using qualitative and quantitative analysis. From the current result, we concluded that ULPE possesses a cardiovascular protective agent as a result of highly contents of different bioactive secondary metabolites which have antioxidant as well as free-radical scavenging and anti-inflammatory activates. Showed the mechanism of ULPE as cardioprotective against heavy metal mixture.

Evaluation of the effect of heat shock protein 70 targeted drugs on cirrhotic cardiomyopathy in biliary cirrhotic rats

AIMS

Liver cirrhosis leads to cirrhotic cardiomyopathy (CCM) and chronotropic incompetence (CI). Heat shock protein 70 (Hsp70) regulates cellular apoptosis and autophagy in stress. Teprenone modulates the Hsp70 and protects against cellular injury. Thus, we aimed to evaluate the effect of teprenone on CI in biliary cirrhotic rats.

MAIN METHODS

Liver cirrhosis was induced in male Wistar rats through bile duct ligation (BDL). The chronotropic responses and QT interval were studied through electrocardiography (ECG) in sham, cirrhotic, and cirrhotic/teprenone (100 mg/kg) pre-treated groups. Brain natriuretic peptide (BNP), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and monocyte chemo-attractant protein-1 (MCP-1), and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were investigated in serum. The Hsp70, B-cell lymphoma 2 (Bcl-2), and B-cell lymphoma 2-associated X protein (Bax) expressions were quantified through real-time polymerase chain reaction (Real-time PCR).

KEY FINDINGS

The chronotropic responses were decreased significantly in cirrhotic and cirrhotic/teprenone groups. The QT interval and serum BNP, TNF-α, IL-6, ALT, AST, and MCP-1 levels were increased significantly in the cirrhotic and decreased significantly, except BNP, in the cirrhotic/teprenone group. The Hsp70 and Bax expressions increased significantly in cirrhotic and decreased significantly in the cirrhotic/teprenone group while the Bcl-2 decreased significantly in cirrhotic and increased significantly in the cirrhotic/teprenone group.

SIGNIFICANCE

Teprenone does not relieve the CI and BNP changes in CCM while other indices are treated. Given that CCM is a multifactorial disease and needs to target other genes and proteins concurrent with Hsp70 to relieve CCM.

Recent advances in cardiac biomarkers detection: From commercial devices to emerging technologies

Although cardiac pathologies are the major cause of death in the world, it remains difficult to provide a reliable diagnosis to prevent heart attacks. Rapid patient care and management in emergencies are critical to prevent dramatic consequences. Thus, relevant biomarkers such as cardiac troponin and natriuretic peptides are currently targeted by commercialized Point-Of-Care immunoassays. Key points still to be addressed concern cost, lack of standardization, and poor specificity, which could limit the reliability of the assays. Consequently, alternatives are emerging to address these issues. New probe molecules such as aptamers or molecularly imprinted polymers should allow a reduction in cost of the assays and an increase in reproducibility. In addition, the assay specificity and reliability could be improved by enabling multiplexing through the detection of several molecular targets in a single device.

Cardioprotective activity of placental growth factor combined with oral supplementation of l-arginine in a rat model of acute myocardial infarction

OBJECTIVE

Exogenous administration of placental growth factor (PlGF) stimulates angiogenesis and improves ventricular remodeling after acute myocardial infarction (AMI), and supplementation with l-arginine ameliorates endothelial function. The objective of the present study was to compare the cardioprotective effects of combination therapy of PlGF and l-arginine with those of direct administration of PlGF alone in a rat model of AMI.

MATERIALS AND METHODS

Fifty male Sprague Dawley rats were randomly divided into five groups: sham group, normal saline group, l-arginine group, PlGF group, and combination group (PlGF + l-arginine). An AMI rat model was established by ligation of the left anterior descending of coronary arteries. After 4 weeks of postligation treatment, cardiac function, scar area, angiogenesis and arteriogenesis, myocardial endothelial nitric oxide synthase (eNOS) and collagen I protein content, and plasma concentration of brain natriuretic peptide (BNP) were studied. Echocardiography, Masson's staining, immunohistochemical analyses, Western blot, and enzyme-linked immunosorbent assay were performed.

RESULTS

Left ventricular ejection fraction (LVEF), left ventricular fraction shortening (LVFS), and capillary and arteriole densities were higher in the PlGF group than in the normal saline group (P<0.01). Scar area, collagen I protein content, and plasma concentration of BNP were decreased in the PlGF group (P<0.01). Myocardial eNOS protein level was elevated in the l-arginine group and PlGF + l-arginine group (P<0.01). Compared with the PlGF group, LVEF, LVFS, myocardial eNOS, and capillary and arteriole densities were higher in the combination group (P<0.01). Scar area, content of collagen I protein, and plasma concentration of BNP were reduced in the combination group (P<0.01).

CONCLUSION

Exogenous administration of PlGF stimulates angiogenesis and improves cardiac function. l-arginine increases the expression of the eNOS protein. PlGF and l-arginine have a more pronounced, synergistic protective effect on myocardial protection compared with that of exogenous PlGF therapy alone.