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Background: The inflammatory responses play a major role in the pathogenesis of acute myocardial infarction (MI). Early inhibition of inflammation may improve post MI cardiac function. The aim of this study was to investigate the effects of tacrolimus on cardiac function, hemodynamic parameters as well as histopathologic and electrocardiographic changes in isoproterenol-induced myocardial infarction. Methods: Male Wistar rats were randomly divided into six groups of control, isoproterenol alone, tacrolimus alone, and isoproterenol plus tacrolimus (0.5, 1 and 2 mg/kg). Isoproterenol (100 mg/kg) was injected subcutaneously for two consecutive days to induce myocardial infarction, and simultaneously tacrolimus was administered orally twice a day for three days. Results and conclusions: Administration of isoproterenol resulted in myocardial edema and necrosis as well as a marked reduction in the left ventricular systolic pressure (LVSP), left ventricular contractility (LVdP/dtmax) and relaxation (LVdP/dtmin) along with a severe elevation in left ventricular end-diastolic pressure (LVEDP). Isoproterenol also elevated the ST-segment and suppressed the R-amplitude and R-R interval on ECG. It was found that all doses of tacrolimus could amend the ECG pattern and ameliorated the isoproterenol induced disturbances in cardiac function. Acute and short term treatment with tacrolimus at dose of 2 mg/kg significantly (P< 0.001) improved LVdP/dtmax from 2712 ±82 in myocardial infarcted rats to 4592 ± 149 mmHg/sec. Similarly, tacrolimus lowered LVEDP from 17.6 ± 0.68 in MI group to the value of 5.6 ±0.22 mmHg (P < 0.001). Furthermore, tacrolimus was found to reduce malondialdehyde concentration in serum and myocardium by 50-70% (P < 0.001). The results of this study showed that acute treatment with tacrolimus, coincided with the occurrence of myocardial infarction, strongly protected the myocardium against the isoproterenol-induced myocardial infarction; where this might be due to the anti-inflammatory properties of tacrolimus. [ABSTRACT FROM AUTHOR]

Background Cynodon dactylon, a valuable medicinal plant, is widely used in Iranian folk medicine for the treatment of various cardiovascular diseases such as heart failure and atherosclerosis. Moreover, its anti-diabetic, anti-cancer and anti-microbial properties have been also reported. Concerning the critical role of angiogenesis in the incidence and progression of tumors and also its protective role in cardiovascular diseases, we investigated the effects of the aqueous extract prepared from the rhizomes of C. dactylon on vascular endothelial growth factor (VEGF) expressions in Human Umbilical Vein Endothelial Cells (HUVECs) and also on angiogenesis in carrageenan induced air-pouch model in rats. Methods In the air-pouch model, carrageenan was injected into an air-pouch on the back of the rats and following an IV injection of carmine red dye on day 6, granulation tissue was processed for the assessment of the dye content. Furthermore, in an in vitro study, angiogenic property of the extract was assessed through its effect on VEGF expression in HUVECs. Results Oral administration of 400 mg/kg/day of the extract significantly increased angiogenesis (p < 0.05) and markedly decreased neutrophil (p < 0.05) and total leukocyte infiltration (p < 0.001) into the granulation tissues. Moreover, the extract increased the expression of total VEGF in HUVECs at a concentration of (100 μl/ml). Conclusion The present study showed that the aqueous extract of C. dactylon promotes angiogenesis probably through stimulating VEGF expression. [ABSTRACT FROM AUTHOR]

Background and the purpose of the study: The objectives of the present study were phytochemical screening and study of the effects of ethanolic extract of aerial parts of Ocimum basilicum (basil) on cardiac functions and histopathological changes in isoproterenol-induced myocardial infarction (MI). Methods: The leaves of the plant were extracted with ethanol by maceration and subjected to colorimetry to determine flavonoids and phenolic compounds. High-performance TLC analysis and subsequent CAMAG's TLC scanning were performed to quantify rosmarinic acid content. Wistar rats were assigned to 6 groups of normal control, sham, isoproterenol, and treatment with 10, 20, and 40 mg/kg of the extract two times per day concurrent with MI induction. A subcutaneous injection of isoproterenol (100 mg/kg/day) for 2 consecutive days was used to induce MI. Results: Phytochemical screening indicated the presence of phenolic compounds (5.36%) and flavonoids (1.86%). Rosmarinic acid was the principal phenolic compound with a 15.74% existence. The ST-segment elevation induced by isoproterenol was significantly suppressed by all doses of the extract. A severe myocardial necrosis and fibrosis with a sharp reduction in left ventricular contractility and a marked increase in left ventricular end-diastolic pressure were seen in the isoproterenol group, all of which were significantly improved by the extract treatment. In addition to in-vitro antioxidant activity, the extract significantly suppressed the elevation of malondialdehyde levels both in the serum and the myocardium. Conclusion: The results of the study demonstrate that Ocimum basilicum strongly protected the myocardium against isoproterenol-induced infarction and suggest that the cardioprotective effects could be related to antioxidative activities. [ABSTRACT FROM AUTHOR]

Background and purpose of the study: Probable antiarrhythmic effects of Cynodon dactylon (L.) pers. (family Poaceae) against ischemia/reperfusion (I/R)-induced arrhythmias were investigated in isolated rat heart. Methods: The hearts were subjected to 30min regional ischemia followed by 30min reperfusion and perfused with hydroalcoholic extract of rhizome of C. dactylon (25, 50, 100 and 200µg/ml). Results: During ischemia, the extract produced marked reduction in the number, duration and incidences of ventricular tachycardia (VT) at 25 and 50µg/ml (p<0.001 and p<0.01, respectively). Total number of ischemic ventricular ectopic beats (VEBs) were lowered by 25-100µg/ml (p<0.001, p<0.001 and p<0.05, respectively). At the reperfusion phase, C. dactylon (25 and 50µg/ml) decreased incidence of VT from 100% (control) to 13 and 33% (p<0.001 and p<0.05) respectively. Duration and number of VT and total VF incidence were also reduced at the same concentration (p<0.05 for all). Perfusion of the extract (25- 100µg/ml) was markedly lowered reversible VF duration from 218±99sec to 0 sec, 0 sec and 10±5sec (p<0.01, p<0.01 and p<0.05) respectively. Moreover, C. dactylon (25 and 50µg/ml) decreased number of total VEBs from 349±73 to 35±17 (p<0.001) and 66±26 (p<0.01). In this study, it was also shown that perfusion of the extract produced a marked and concentration-dependent positive inotropic effect. Conclusion: The findings of this study indicate that C. dactylon produce protective effects against I/R-induced arrhythmias in isolated rat hearts probably by increase in the myocardial contractility and as a result by improvement of hemodynamic factors. [ABSTRACT FROM AUTHOR]

Background: Stachys schtschegleevii Sosn. (commonly known as "Poulk" and "Sonbeleh Arasbarani") and Stachys inflate Benth. ("Sonbeleh Arghavani") are most widely used for medicinal purposes. Stachys schtschegleevii Sosn.( Lamiaceae) is widespread in North West of Iran and have been used traditionally to treat infections, asthma, rheumatic and other inflammatory disorders. In the present studies the anti-inflammatory activity of hydro-alcoholic extracts of both flowering and sterile tops of S. schtschegleevii were investigated. Material and Methods: The methanolic extract of the sterile aerial parts was partitionated between chloroform, ethyl acetate and n-butanol. The column chromatography (CC) on silica gel was used to fractionate the ethyl acetate extract and the anti-inflammatory effects of each main fraction were evaluated by carrageenan-induced rat paw oedema assay. The reversed-phase preparative HPLC was used to isolate compounds from the active fractions and their structure (1-3) were elucidated by spectroscopic means. The ethyl acetate portion was fractionated into 11 major fractions. Results: the most prominent anti-inflammatory effect was observed with fractions 8 to 10 of the ethyl acetate portion. Fraction 8 abolished considerably the mean maximal responses of inflammation from 87.00±3.5% in control to 61.10±7.2% (p<0.001) and 62.10±3.6% (p<0.001) in 15 and 30 mg/kg fraction-treated groups, respectively. Preparative-HPLC analyses of fractions 5 and 8-10 led to the isolation and identification of three major compounds, chrysoeriol 7-O-β-[6"-(p- coumaroyl)]-glucoside (1), apigenin 7-O-β-[6"-(p- coumaroyl)]-glucoside (2), and acteoside (3). Conclusion: It seems that caffeic acid derivatives such as acteoside may be implicated in anti-inflammatory effect of Stachys schetschegleevii Sosn. [ABSTRACT FROM AUTHOR]

The protective and anti-inflammatory effects of azo and azo-linked polymeric prodrugs of 5-aminosalicylic acid (5-ASA) on acetic acid induced colitis in rats were investigated. Three azo prodrugs; 4,4'-dihydroxy-azobenzene-3-carboxilic acid (azo compound I), 4-hydroxy-azobenzene-3,4'- dicarboxilic acid (azo compound II), 4,4'-dihydroxy-3'-formyl-azobenzene-3-carboxylic acid (azo compound III) and their polyethylene glycol (PEG 6000) derivatives were synthesized. Rats were pretreated orally (1 hour prior to induction of colitis) with sulfasalazin (300 mg/kg), azo compounds I, II, III and polyethylene glycol conjugates of azo compounds II and III in doses which had the same amount of 5-ASA as sulfasalazin contains. The colonic damage was examined 24 hours later and characterized by gross microscopic injury and colonic edema. Among prodrugs only azo compound III (215 mg/kg) produced a significant (p&lt'0.01) protective effect against colonic injury comparable with sulfasalazin. Doubling the dose (430 mg/kg) showed more anti-colitis effects. Polyethylene glycol conjugate of azo compounds II and III also showed reduction in the extent of the cell death and tissue disorganization similar to sulfasalazin. While neither sulfasalazin, nor azo compound II and its PEG polymer produced anti-edema effects, both azo compound III and its PEG polymer decreased colon edema significantly (p<0.05). Histological examinations also indicated a marked reduction in tissue injury and inhibition in neutrophil infiltration in rats treated with azo compound III and PEG conjugates of azo compounds II and III. Results of this investigation provide experimental evidence supporting new cytoprotective, anti-inflammatory and anti-edema properties of the azo derivatives of 5-ASA and their PEGylated prodrugs. [ABSTRACT FROM AUTHOR]