Abstract
This study evaluated the effect of
Crataegus aronia (C. aronia)
aqueous extract on cardiac substrate utilization and insulin signaling in adult male healthy Wistar rats. Rats (n = 18/group) were either administered normal saline (vehicle) or treated with
C. aronia
aqueous extract (200 mg/kg) for 7 days, daily. Fasting plasma glucose and insulin levels were not significantly changed in
C. aronia
-treated rats but were significantly reduced after both the intraperitoneal glucose or insulin tolerance tests. Besides,
C. aronia
significantly increased the left ventricular (LV) activities of phosphofructokinase (PFK) and pyruvate dehydrogenase (PDH), two markers of glycolysis and glucose oxidation, respectively, and suppressed the levels of pyruvate dehydrogenase kinase 4 (PDK4), an inhibitor of PDH. Concomitantly, it significantly reduced the LV levels of carnitine palmitoyltransferase 1 (CPT1) and PPARĪ±, two markers of fatty acid (FAs) oxidations. Under basal and insulin stimulation,
C. aronia
aqueous extract boosted insulin signaling in the LV of rats by increasing the protein levels of p-IRS (Tyr
612
) and p-Akt (Ser
473
) and suppressing protein levels of p-mTOR (Ser 2448) and p-IRS (Ser
307
). In parallel,
C. aronia
also increased the protein levels of GLUT-4 in the membrane fraction of the treated LVs. All these effects were also associated with a significant increase in AMPK activity (phosphorylation at Thr
172
), a major energy modulator that stimulates glucose utilization. In conclusion, short-term administration of C.
aronia
aqueous extract shifts the cardiac metabolism toward glucose utilization, thus making this plant a potential therapeutic medication in cardiac disorders with impaired metabolism.