Cardiac insulin-like growth factor-1 and cyclins gene expression in canine models of ischemic or overpacing cardiomyopathy

<p>Abstract</p> <p>Background</p> <p>Insulin-like growth factor-1 (IGF-1), transforming growth factor β (TGFβ) and cyclins are thought to play a role in myocardial hypertrophic response to insults. We investigated these signaling pathways in canine models of ischemic or overpacing-induced cardiomyopathy.</p> <p>Methods</p> <p>Echocardiographic recordings and myocardial sampling for measurements of gene expressions of IGF-1, its receptor (IGF-1R), TGFβ and of cyclins A, B, D1, D2, D3 and E, were obtained in 8 dogs with a healed myocardial infarction, 8 dogs after 7 weeks of overpacing and in 7 healthy control dogs.</p> <p>Results</p> <p>Ischemic cardiomyopathy was characterized by moderate left ventricular systolic dysfunction and eccentric hypertrophy, with increased expressions of IGF-1, IGF-1R and cyclins B, D1, D3 and E. Tachycardiomyopathy was characterized by severe left ventricular systolic dysfunction and dilation with no identifiable hypertrophic response. In the latter model, only IGF-1 was overexpressed while IGF-1R, cyclins B, D1, D3 and E stayed unchanged as compared to controls. The expressions of TGFβ, cyclins A and D2 were comparable in the 3 groups. The expression of IGF-1R was correlated with the thickness of the interventricular septum, in systole and diastole, and to cyclins B, D1, D3 and E expression.</p> <p>Conclusion</p> <p>These results agree with the notion that IGF-1/IGF-1R and cyclins are involved in the hypertrophic response observed in cardiomyopathies.</p

Cardioprotective effects of Fenugreek (Trigonella foenum-graceum) seed extract in streptozotocin induced diabetic rats

Introduction: Inadequate control of diabetes mellitus (DM) leads to considerable cardiovascular implications like diabetic cardiomyopathy (DCM). Cardiomyocyte apoptosis is one of the main mechanisms of DCM pathogenesis associated with hyperglycemia, oxidative stress, inflammation, hyperlipidemia and several other factors. Trigonella foenum-graecum (Fenugreek) has been long used as a traditional medicine and has many therapeutic effects, including anti-diabetic, anti-hyperlipidemia, anti-inflammatory and anti-oxidant properties. The current study aimed to investigate cardioprotective effects of fenugreek seed on diabetic rats. Methods: Diabetes was induced in forty-two male rats by injection of streptozotocin (STZ) (60 mg/ kg). Diabetic animals were treated with three different doses of fenugreek seed extract (50, 100 and 200 mg/kg) or metformin (300 mg/kg) for six weeks by gavage. Nondiabetic rats served as controls. Glucose, cholesterol, and triglycerides levels were measured in the blood samples, and oxidative stress markers as well as gene expression of ICAM1, Bax and Bcl2 were assessed in the cardiac tissues of the experimental groups. Results: Diabetic rats exhibited increased serum glucose, cholesterol and triglycerides levels, elevated markers of oxidative stress thiobarbituric acid–reacting substances (TBARS) levels , total thiol groups (SH), catalase (CAT) and superoxide dismutase (SOD) activity, and enhanced apoptosis cell death (ratio of Bax/Bcl2). Fenugreek seed extract considerably improved metabolism abnormalities, attenuated oxidative stress and diminished apoptosis index. Conclusion: Our study suggests that fenugreek seed may protect the cardiac structure in STZ-induced diabetic rats by attenuating oxidative stress and apoptosis

The effects of vitamin D on cardiovascular damage induced by lipopolysaccharides in rats

Introduction: Inflammation and oxidative stress are contributed to cardiovascular diseases. Vitamin D (Vit D) has antioxidant and anti-inflammatory properties. In the current research, the effect of Vit D on cardiac fibrosis and inflammation, and oxidative stress indicators in cardiovascular tissues was studied in lipopolysaccharides(LPS) injected rats. Methods: Rats were distributed into 5 groups and were treated for 2 weeks. Control: received vehicle(saline supplemented with tween-80) instead of Vit D and saline instead of LPS, LPS: treated by 1 mg/kg of LPS and was given vehicle instead of Vit D, LPS-Vit D groups: received 3 doses of Vit D (100, 1000, and 10000 IU/kg) of Vit D in addition to LPS. Vit D was dissolved in saline supplemented with tween-80 (final concentration 0.1%) and LPS was dissolved in saline. The white blood cell (WBC) was counted. Oxidative stress markers were determined in serum, aorta, and heart. Cardiac tissue fibrosis was also estimated using Masson’s trichrome staining method. Results: WBC and malondialdehyde (MDA) were higher in the LPS group than the control group, whereas the thiol content, superoxide dismutase (SOD), and catalase (CAT) were lower in the LPS group than the control group (P<0.01 and P<0.001). Administration of Vit D decreased WBC (P<0.001) and MDA (P<0.05 and P<0.001) while enhanced thiol (dose 10000 IU/Kg) (P<0.001), SOD (dose 10000 IU/kg) (P<0.001), and CAT (P<0.05 and P<0.001) compared to the LPS group. All doses of Vit D also decreased cardiac fibrosis compared to the LPS group (P<0.001). Conclusion: Vit D protected the cardiovascular against the detrimental effect of LPS. This cardiovascular protection can be attributed to the antioxidant and anti-inflammatory properties of Vit D

Ventricular-arterial uncoupling in heart failure with preserved ejection fraction after myocardial infarction in dogs - invasive versus echocardiographic evaluation

Heart failure with preserved left ventricular ejection fraction and abnormal diastolic function is commonly observed after recovery from an acute myocardial infarction. The aim of this study was to investigate the physiopathology of heart failure with preserved ejection fraction in a model of healed myocardial infarction in dogs.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Extract from Teucrium polium L. Protects Rat Heart against Oxidative Stress Induced by Ischemic–reperfusion Injury

Background: The deleterious effect of oxidative stress on myocardial ischemia–reperfusion (I/R) has already been shown in previous studies. Since Teucrium polium has anti-oxidative and cardio-protective properties, the aim of this study was to investigate the effects of this plant on I/R injuries in the isolated rat heart. Materials and Methods: The myocardial I/R injury of rat was created by Langendorff retrograde perfusion technology. The heart was preperfused with Krebs–Henseleit (K-H) solution containing T. polium extract for 20 min before 20 min global ischemia, and then the reperfusion with K-H bicarbonate buffer was conducted for 40 min. The left ventricular developed pressure and the maximum up/down rate of the left ventricular pressure (±dp/dtmax) were recorded by physiological recorder as the myocardial function. Lactate dehydrogenase (LDH) and creatine kinase (CK) activities in the effluent were measured to determine the myocardial injury degree. Thiobarbituric acid reactive substances (TBARS), total thiol groups (−SH), superoxide anion dismutase (SOD), and catalase (CAT) in myocardial tissue were detected to determine the oxidative stress degree. Results: The results showed that the pretreatment with T. polium significantly enhanced cardiac parameters and the coronary artery flow, decreased the LDH, CK activities, and TBARS level, whereas it increased − SH groups, SOD and CAT activities. Conclusions: Our findings indicated that T. polium could provide protection for heart against the I/R injury which may be related to the improvement of myocardial oxidative stress states

Hydroalcoholic extract of Crocus sativus effects on bronchial inflammatory cells in ovalbumin sensitized rats

Objective: Inflammation is one of the major components of asthma. Our aim was to evaluate the effects of C. sativus extract on total and differential white blood cells (WBC) count in lung lavage fluid (LLF) of ovalbumin-sensitized rats. Materials and Methods: Forty rats were divided into five groups (n = 8 for each group) as control (C), sensitized with injection and inhalation of ovalbumin (OA) alone (S), and three groups of sensitized and treated with different doses of C. sativus extract (S+50EX, S+100EX, and S+200EX groups). Total and differential WBC counts of LLF were evaluated in control, sensitized, and treated sensitized groups. Results: Total WBC count, neutrophil, and eosinophil percentage in LLF were increased in sensitized animals compared with the control group (

Preventive effects of hydroalcoholic extract of saffron on hematological parameters of experimental asthmatic rats

Objective: Asthma is a chronic inflammatory disease of the respiratory airways distinguished by edema and infiltration of inflammatory immune cells. To test our hypothesis about the anti-inflammatory effect of saffron, we examined effects of Crocus sativus (C. sativus) extract as a prophylactic anti-inflammatory agent in sensitized rats. Materials and Methods: To induce experimental asthma, rats were sensitized with injection and inhalation of ovalbumin (OA). Forty male Wistar rats were divided into 5 groups (n=8 for each): control, sensitized (asthma), and sensitized and pretreated with three different concentrations of extract, 50, 100, and 200 mg/kg, 2 times a week (group asthma+50EX, group asthma+100EX, and group asthma+200EX). After 32 days, total white blood cells (WBC) counts, red blood cells (RBC), and platelet counts in blood were examined. Results: Total WBC number and eosinophil and neutrophil percentage in blood were increased, but lymphocyte decreased in sensitized animals compared with those of control group (pConclusion: Our findings indicated that the extract of C. sativus could be useful to prevent asthma as an anti-inflammatory treatment

The effects of hydroalcoholic extract of Nigella sativa seed on oxidative stress in hippocampus of STZ-induced diabetic rats

Objective: Oxidative stress plays an important role in the etiology of diabetic complications. Diabetes impairs hippocampus neurogenesis, synaptic plasticity, and learning. The aim of this study was to investigate the effects of hydroalcoholic extract of Nigella sativa seed on oxidative stress in STZ-induced diabetic rats' hippocampus. Materials and Methods: Diabetes induced by 60 mg/kg STZ, i.p, and the rats were divided into five experimental groups (n=8-10 in each group) including control (received 0.5 ml normal saline), untreated STZ-diabetic (received 0.5 ml normal saline), and treated rats received Nigella sativa extract (200 and 400 mg/kg) or metformin (300 mg/kg) by gavage for 42 days. Serum glucose concentration and body weight as well as hippocampus tissue malondialdehyde and thiollevels were determined by calorimetric assay. Results: Serum glucose level in the diabetic rats treated with 200 mg/kg Nigella sativaextract at the days 24 and 45 decreased in comparison to untreated diabetic group (

Endothelium-Independent Vasorelaxant Effects of Hydroalcoholic Extract from Nigella sativa Seed in Rat Aorta: The Roles of Ca2+ and K+ Channels

Objective. The aim of this study was to elucidate the mechanism(s) responsible for the vasorelaxant effect of Nigella sativa (N. sativa). Methods. The activity of different concentrations of N. sativa extract was evaluated on contractile responses of isolated aorta to KCl and phenylephrine (PE). Results. The extract (2–14 mg/mL) induced a concentration dependent relaxation both in endothelium-intact and endothelium-denuded aortic rings precontracted by PE (10−6 M) and KCl (6 × 10−2 M). Extract reduced PE- and KCl-induced contractions in presence of cumulative concentrations of calcium (10−5–10−2 M) significantly. L-NAME and indomethacin had no effect on vasorelaxation effect of extract in PE-induced contraction. Diltiazem and heparin reduced significantly this vasorelaxation at a concentration of 14 mg/mL of extract; however, N. sativa-induced relaxation was not affected by ruthenium red. Tetraethylammonium chloride reduced the extract-induced relaxation in concentrations of 2–6 mg/mL of extract significantly but glibenclamide reduced this relaxative effect in all concentrations of extract. Conclusions. The inhibitory effect of N. sativa seed extract on the contraction induced by PE and KCl was endothelium-independent. This relaxation was mediated mainly through the inhibition of Ca2+ and KATP channels and also intracellular calcium release

Mechanism of vasorelaxation induced by Achillea wilhelmsii in rat isolated thoracic aorta

Background: Achillea wilhelmsii (A. wilhelmsii) is used in Iraninan folk medicine for the treatment of hypertension; also, in previous reports, the hypotensive and antihypertensive effects of this plant have been indicated. The aim of the present study is to investigate the vasorelaxant effect of the hydroalcholic extract of A. wilhelmsii and its underlying mechanisms in isolated rat aorta. Materials and Methods: The effect of the hydroalcholic A. wilhelmsii extract was tested on the contractile response of Wistar rat aorta induced by potassium chloride (KCl) and phenylephrine (PE) using a pressure transducer that is connected to the PowerLab. Results: The cumulative concentrations of A. wilhelmsii (0.5-8 mg/ml) induced a vasorelaxation both in endothelium-intact and endothelium-denuded aortas precontracted by high K + (6 Χ 10−2 M) or 10−6 M PE. A. wilhelmsii, at a concentration of 4 mg/ml, reduced Ca 2+ -induced contraction (P < 0.001 vs. control) after PE or KCl had generated a stable contraction in the Ca 2+ -free solution. Furthermore, after incubation with diltiazem, the vasorelaxant effect of A. wilhelmsii reduced in the endothelium-denuded aortas precontracted by PE or KCl (P < 0.001 vs. control). In contrast, A. wilhelmsii-induced relaxation was not affected by glibenclamide, BaCl 2 , ruthenium red, methylene blue, or heparin. Conclusions: The results showed that A. wilhelmsii had a vasorelaxation effect, which was not endothelium-dependent. The relaxation was mediated by inhibition of extracellular Ca 2+ influx through voltage- and receptor-operated Ca 2+ channels (VDDCs and ROCCs) in vascular smooth muscle cells