Tea polyphenols promote cardiac function and energy metabolism in ex vivo rat heart with ischemic/reperfusion injury and inhibit calcium inward current in cultured rat cardiac myocytes.

Abstract

OBJECTIVE:

To investigate the protective effects of tea polyphenols (TP) against myocardial ischemia/reperfusion (IR) injuries and explore the possible mechanisms.

METHODS:

Langendorff-perfused rat hearts were subjected to ischemia for 30 min followed by reperfusion for another 30 min. Myocardial function indices were measured by a left ventricular cannula via a pressure transducer connected to the polygraph in isolated Langendorff hearts and energy metabolism was measured using (31)P nuclear magnetic resonance (NMR) spectroscopy. Whole-cell atch-clamp technique was used to record calcium inward current (I(Ca-L)) in cultured rat cardiac myocytes.

RESULTS:

Compared with the control hearts, the ex vivo rat hearts with 2.5 mg/L TP treatment showed significantly increased left ventricular developed pressure (LVDP), maximal rise rate of LVDP (+dp/d(tmax)), maximal fall rate of LVDP (-dp/dt(max)), and coronary flow (CF) (P<0.05). During both cardiac ischemia and reperfusion phase, ATP and PCr levels were elevated significantly in TP-treated hearts compared with those in the control hearts (P<0.05). In cultured rat cardiac myocytes, ICa-L was remarkably decreased by TP at the doses of 2.5 and 5.0 mg/L (P<0.01).

CONCLUSION:

Our results support a possible protective role of TP against myocardial IR injury by improving myocardial energy metabolism and inhibiting I(Ca-L) in the cardiac myocytes.

• Authors: Hua-Jin Dong, Jie Li, Hao Zhan, Yang Li, Rui-Bin Su
• Journal: Nan fang yi ke da xue xue bao = Journal of Southern Medical University (Nan Fang Yi Ke Da Xue Xue Bao) Vol. 36 Issue 5 Pg. 604-8 (May 2016) ISSN: 1673-4254 [Print] China
• PMID: 27222171 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Calcium Channels
• Polyphenols
• Tea
• Calcium

Topics

• Animals
• Calcium (metabolism)
• Calcium Channels (metabolism)
• Cells, Cultured
• Energy Metabolism
• Heart (drug effects)
• In Vitro Techniques
• Myocardial Reperfusion Injury
• Myocardium (metabolism)
• Myocytes, Cardiac (drug effects, metabolism)
• Polyphenols (pharmacology)
• Rats
• Tea (chemistry)