Luteolin Exerts Cardioprotective Effects through Improving Sarcoplasmic Reticulum Ca2+-ATPase Activity in Rats during IschemiaReperfusion In Vivo

Abstract EN

The flavonoid luteolin exists in many types of fruits, vegetables, and medicinal herbs.

Our previous studies have demonstrated that luteolin reduced ischemia/reperfusion (I/R) injury in vitro, which was related with sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) activity.

However, the effects of luteolin on SERCA2a activity during I/R in vivo remain unclear.

To investigate whether luteolin exerts cardioprotective effects and to monitor changes in SERCA2a expression and activity levels in vivo during I/R, we created a myocardial I/R rat model by ligating the coronary artery.

We demonstrated that luteolin could reduce the myocardial infarct size, lactate dehydrogenase release, and apoptosis during I/R injury in vivo.

Furthermore, we found that luteolin inhibited the I/R-induced decrease in SERCA2a activity in vivo.

However, neither I/R nor luteolin altered SERCA2a expression levels in myocardiocytes.

Moreover, the PI3K/Akt signaling pathway played a vital role in this mechanism.

In conclusion, the present study has confirmed for the first time that luteolin yields cardioprotective effects against I/R injury by inhibiting the I/R-induced decrease in SERCA2a activity partially via the PI3K/Akt signaling pathway in vivo, independent of SERCA2a protein level regulation.

SERCA2a activity presents a novel biomarker to assess the progress of I/R injury in experimental research and clinical applications.