Cardioprotective effects of Achillea wilhelmsii on the isolated rat heart in ischemia-reperfusion

Context

There are some reports about protective effects of Achillea on the heart.

Objective

We investigated the effect of Achillea wilhelmsii extract on cardiac function during ischemia–reperfusion (I/R) injury in the isolated rat heart.

Materials and methods

60 male Wistar rats were randomly divided into 6 groups; 1: Control group, 2: Control-ischemia (CI) 3: vitamin C (10 mg/kg), 4–6: Extract groups (E 100, E 200 and E 400 mg/kg). The animals received normal saline, vitamin C or A. wilhelmsii extract orally for 4 weeks. At the end of the treatment, the hearts were subjected to in vitro I/R Injury (20 min of global ischemia, followed by 40 min of reperfusion, Langendorff's mode). Heart rate (HR) and left ventricular pressure (LVP) were measured using a pressure transducer connected to a data acquisition system. Lactate dehydrogenase (LDH) and creatine kinase (CK) activities in the effluent were measured to determine the myocardial injury degree. The malondialdehyde (MDA), total thiol groups (-SH), superoxide anion dismutase (SOD) and catalase (CAT) in myocardial tissue were detected to determine the oxidative stress degree.

Results

Pretreatment with Achillea wilhlemsii significantly decreased the LDH, CK activities, and MDA level, while it increased the LVDP, ±dp/dt_max, rate-pressure product (RPP), SH groups, SOD and CAT activities, and also the coronary artery flow.

Discussion and conclusion

Our findings indicated that Achillea wilhelmsii could provide protection for heart against the I/R injury which may be related to the improvement of myocardial oxidative stress states.

Investigation of apoptosis in a canine model of chronic heart failure induced by tachycardia

Participation of apoptosis during the development of pacing-induced dilated cardiomyopathy is not fully understood. After 7 weeks rapid right ventricular pacing, gene expressions of Bax, Bcl-2 and Caspase-3 were measured by RTQ-PCR from interventricular septum biopsies that were taken weekly in 21 beagle dogs during the development of heart failure. We evaluated protein levels of these genes by Western blot and DNA fragmentation by TUNEL method from autopsy samples. Gene expression of Bax remained unchanged during the pacing period; Bcl-2 mRNA expression transiently decreased in moderate heart failure and their ratio (Bcl-2/Bax) was not significantly altered. Caspase-3 gene expression increased in heart failure. Compared to the control group, expression of Bax and Bcl-2 proteins and their ratio were increased in dogs only after 4 weeks of pacing. No band of activated Caspase was found in the normal nor in the paced myocardium. In the TUNEL assay there was no significant difference between numbers of apoptotic cells in any of the groups, although a few TUNEL-positive cells were detected in the paced groups. Our results are not in favour of apoptosis in the pathogenesis of heart failure in this model and may be it could be attributed to activation of other systems.